Short answer
Islam teaches that no human being is divine. The Qur'an says every being in the heavens and the earth comes to God (﷾) as a servant. It told the Prophet Muhammad (ﷺ) himself to say: "I am but a man like you." No prophet may tell people to worship him. The Japanese state once taught otherwise. A commentary on its 1889 constitution called the emperor "Heaven-descended, divine and sacred". On 1 January 1946 a rescript, a formal statement in the emperor's name, said something new. It said the ties between emperor and people were not based on "the false conception that the Emperor is divine". Islam's teaching does not rest on any rescript. It holds for every human being, kings and prophets alike. Honour belongs to people, and worship belongs to God (﷾) alone.
Full explanation
No human being is divine
Islam answers this question for every human being, not only for one. The Qur'an says that every being in the heavens and the earth comes to God (﷾) as a servant. It told the Prophet Muhammad (ﷺ) to say: "I am but a man like you". It is revealed to him that God (﷾) is One. He was also told to say that he has no power to bring good or harm even to himself, except as God (﷾) wills. The Qur'an says no man given a Book and prophethood would tell people to worship him. Nor would he tell them to take angels and prophets as lords. The Prophet (ﷺ) said: do not over-praise me; I am only a servant, so call me the servant of Allah (﷾) and His Messenger.
“Not one of the beings in the heavens and the earth but must come to (Allah) Most Gracious as a servant.”
“Say thou: "I am but a man like you: It is revealed to me by Inspiration, that your Allah is one Allah: so stand true to Him, and ask for His Forgiveness." And woe to those who join gods with Allah,-”
“Say: "I am but a man like yourselves, (but) the inspiration has come to me, that your Allah is one Allah: whoever expects to meet his Lord, let him work righteousness, and, in the worship of his Lord, admit no one as partner.”
“Say: "I have no power over any good or harm to myself except as Allah willeth. If I had knowledge of the unseen, I should have multiplied all good, and no evil should have touched me: I am but a warner, and a bringer of glad tidings to those who have faith."”
“It is not (possible) that a man, to whom is given the Book, and Wisdom, and the prophetic office, should say to people: "Be ye my worshippers rather than Allah's": on the contrary (He would say) "Be ye worshippers of Him Who is truly the Cherisher of all: For ye have taught the Book and ye have studied it earnestly." Nor would he instruct you to take angels and prophets for Lords and patrons. What! would he bid you to unbelief after ye have bowed your will (To Allah in Islam)?”
Umar reports that he heard the Prophet (ﷺ) say: do not over-praise me as the Christians over-praised the son of Mary; I am only a servant, so call me the servant of Allah and His Messenger.
The lesson of the Prophet's (ﷺ) death
When the Prophet (ﷺ) died, Umar, one of his leading companions, could not believe it. Abu Bakr, his closest companion, spoke to the people. He said: whoever worshipped Muhammad, Muhammad is dead; whoever worshipped Allah (﷾), Allah (﷾) is alive and never dies. Then he recited verses of the Qur'an, among them: "Muhammad is no more than a messenger". A human being is born and dies. Worship belongs only to the One who never dies.
Aisha reports that when the Prophet (ﷺ) died, Umar insisted he was not dead. Abu Bakr went in, uncovered his face and kissed him, then came out and told the people: whoever worshipped Muhammad, Muhammad is dead; whoever worshipped Allah, Allah is alive and never dies. He then recited Qur'an 39:30 and 3:144.
“Muhammad is no more than a messenger: many Were the messenger that passed away before him. If he died or were slain, will ye then Turn back on your heels? If any did turn back on his heels, not the least harm will he do to Allah; but Allah (on the other hand) will swiftly reward those who (serve Him) with gratitude.”
What the state taught, 1889-1945
Japan's first modern constitution, the Meiji Constitution of 1889, says in Article 3: "The Emperor is sacred and inviolable." Ito Hirobumi, one of the men who wrote it, also wrote a commentary on it. On this article he wrote: "The Emperor is Heaven-descended, divine and sacred; He is pre-eminent above all His subjects." He began with a line about the Sacred Throne, which he says comes from the Kojiki, Japan's oldest chronicle. The old books trace the emperors' family line back to Amaterasu. Shinto honours her as the kami of the sun. Kami are the sacred beings and powers that Shinto honours. Shinto scholars say kami are not "gods" in the Western sense. The Nihon Shoki, a chronicle of 720, sets several versions side by side. In one of them, Amaterasu tells her grandchild that her descendants shall be lords of the land.
“The Emperor is sacred and inviolable.”
““The Sacred Throne was established at the time when the heavens and the earth became separated” (Kojiki). The Emperor is Heaven-descended, divine and sacred; He is pre-eminent above all His subjects. He must be reverenced and is inviolable. He has indeed to pay due respect to the law, but the law has no power to hold Him accountable to it.”
“Then she commanded her August Grandchild, saying:—'This Reed-plain-1500-autumns-fair-rice-ear Land is the region which my descendants shall be lords of. Do thou, my August Grandchild, proceed thither and govern it.”
A Kokugakuin University paper on how kami is understood. It notes that kami is usually translated "god", but that it is often claimed that the Japanese word and the English word are quite different concepts, and it contrasts the monotheism of the Jewish and Christian tradition with the polytheistic ideas of Shinto.
What changed in 1945 and 1946
On 15 December 1945 the Allied headquarters in Tokyo issued the Shinto Directive (SCAPIN-448). It ended state support for Shinto. It also ruled that "the dissemination of Shinto doctrines" in schools "supported wholly or in part by public funds is prohibited". Then a rescript of 1 January 1946 spoke of the ties between the emperor and the people. In the English released with it, it said: "They do not depend upon mere legends and myths. They are not predicated on the false conception that the Emperor is divine ..." The Japanese word rendered "divine" is akitsumikami, a "manifest kami": a kami in human form. The rescript says nothing about descent from Amaterasu.
“The dissemination of Shinto doctrines in any form by any means in any educational institution supported wholly or in part by public funds is prohibited and will cease immediately.”
“The ties between us and our people have always stood upon mutual trust and affection. They do not depend upon mere legends and myths. They are not predicated on the false conception that the Emperor is divine”
Honour for people, worship for God (﷾)
Japan keeps a national holiday, Respect for the Aged Day (Keiro no Hi), to honour the elderly. Islam commands honour for parents in old age, with gentle words and humility. But the same passage begins: worship none but God (﷾). Honour is due to people, and worship is due to God (﷾) alone. Islam also gives no one rank before God (﷾) by birth. The Qur'an says the most honoured is the most righteous. The Prophet (ﷺ) said that whoever is held back by his deeds will not be hurried forward by his lineage.
The Act sets the purpose of each national holiday. Respect for the Aged Day (Keiro no Hi), the third Monday of September, is to respect and love the elderly who have served society for many years, and to celebrate their long life. Children's Day (5 May) is to respect children as persons, to seek their happiness, and to thank mothers. Greenery Day (4 May) is to draw close to nature and be thankful for its blessings.
“Thy Lord hath decreed that ye worship none but Him, and that ye be kind to parents. Whether one or both of them attain old age in thy life, say not to them a word of contempt, nor repel them, but address them in terms of honour. And, out of kindness, lower to them the wing of humility, and say: "My Lord! bestow on them thy Mercy even as they cherished me in childhood."”
“O mankind! We created you from a single (pair) of a male and a female, and made you into nations and tribes, that ye may know each other (not that ye may despise (each other). Verily the most honoured of you in the sight of Allah is (he who is) the most righteous of you. And Allah has full knowledge and is well acquainted (with all things).”
Abu Hurayra reports a longer saying of the Prophet (ﷺ) about good deeds and their reward. Among them: whoever follows a path in search of knowledge, Allah makes easy for him a path to Paradise; and when people gather in a mosque to recite the Qur'an and study it together, tranquillity descends on them, mercy covers them and the angels surround them. It ends: whoever is held back by his deeds will not be hurried forward by his lineage.
How to weigh the answer
Islam's teaching on this does not depend on any state or any rescript. It comes from a Book that asks to be read with care. That Book was brought by Muhammad (ﷺ), the last of the Prophets, who was sent to all people. Islam is a complete way of life, with one Creator at its centre and every human being His servant. The first step is to read the Qur'an for yourself and to consider the man who brought it.
“Do they not consider the Qur'an (with care)? Had it been from other Than Allah, they would surely have found therein Much discrepancy.”
“Say: "O men! I am sent unto you all, as the Messenger of Allah, to Whom belongeth the dominion of the heavens and the earth: there is no god but He: it is He That giveth both life and death. So believe in Allah and His Messenger, the Unlettered Prophet, who believeth in Allah and His words: follow him that (so) ye may be guided."”
“Muhammad is not the father of any of your men, but (he is) the Messenger of Allah, and the Seal of the Prophets: and Allah has full knowledge of all things.”
Five replies answered
Constitution of the Empire of Japan (Meiji Constitution, 1889), Article 3
“The Emperor is sacred and inviolable.”
Cited for
"Sacred and inviolable" was a legal formula found in European constitutions of the time. It meant the monarch could not be sued, not that he was divine.
The response
For Article 3 on its own, that reading is fair. Ito's commentary gives that legal sense too: the law has no power to hold the emperor to account. But the same paragraph says more. In the English of Miyoji Ito, who helped draft the constitution, it calls the emperor "Heaven-descended, divine and sacred". That is why this page quotes the commentary, not the article alone.
Where it lands — The claim of divinity rests on the commentary, in the English of one of the constitution's drafters, not on the legal formula of Article 3.
Imperial Rescript of 1 January 1946 (the "Humanity Declaration"), English text released with it
“The ties between us and our people have always stood upon mutual trust and affection. They do not depend upon mere legends and myths. They are not predicated on the false conception that the Emperor is divine”
Cited for
The 1946 rescript never says "I am not a god". It speaks only of the ties between the emperor and the people.
The response
This page quotes the rescript's words as they stand. It says those ties are not predicated on "the false conception that the Emperor is divine". The Japanese word is akitsumikami, a manifest kami. The rescript says nothing about descent from Amaterasu. Islam's answer does not depend on how the rescript is read. It rests on the Qur'an: every being comes to God (﷾) as a servant.
Where it lands — The rescript is quoted exactly. Islam's teaching stands on the Qur'an, whatever reading of the rescript one prefers.
Perspectives toward Understanding the Concept of Kami
A Kokugakuin University paper on how kami is understood. It notes that kami is usually translated "god", but that it is often claimed that the Japanese word and the English word are quite different concepts, and it contrasts the monotheism of the Jewish and Christian tradition with the polytheistic ideas of Shinto.
Cited for
A kami is not God in the Western sense. Akitsumikami meant a kami in human form, not the Creator, so no one claimed the emperor made the world.
The response
Shinto scholars do say that kami are not "gods" in the Western sense. But the Qur'an does not only forbid calling a man the Creator. It says not even a prophet may tell people to worship him, or to take angels and prophets as lords. If a prophet may not, no other man may. Reverence that belongs to God (﷾) is His alone.
Where it lands — Islam forbids taking any human being as a lord beside God (﷾), not only calling him the Creator.
Sahih Muslim 2699 — Kitab al-Dhikr wa al-Du'a wa al-Tawba wa al-Istighfar (Remembrance, Supplication, Repentance and Seeking Forgiveness), hadith 2699
Abu Hurayra reports a longer saying of the Prophet (ﷺ) about good deeds and their reward. Among them: whoever follows a path in search of knowledge, Allah makes easy for him a path to Paradise; and when people gather in a mosque to recite the Qur'an and study it together, tranquillity descends on them, mercy covers them and the angels surround them. It ends: whoever is held back by his deeds will not be hurried forward by his lineage.
Cited for
Muslims revere the Prophet's (ﷺ) family and lineage, so Islam honours descent too.
The response
Muslims love the Prophet's (ﷺ) family, but no one shares in God's (﷾) divinity through descent. Nor does descent give rank before Him. The Qur'an says the most honoured is the most righteous. The Prophet (ﷺ) said that whoever is held back by his deeds will not be hurried forward by his lineage.
Where it lands — In Islam lineage gives no rank before God (﷾); deeds and righteousness do.
Sahih al-Bukhari 3445 — Kitab Ahadith al-Anbiya (Book of the Prophets), hadith 3445
Umar reports that he heard the Prophet (ﷺ) say: do not over-praise me as the Christians over-praised the son of Mary; I am only a servant, so call me the servant of Allah and His Messenger.
Cited for
Muslims love the Prophet (ﷺ) above all people and send blessings on him. That is the same reverence.
The response
Loving him is not worshipping him. Sending blessings on the Prophet (ﷺ) is itself a prayer to God (﷾): Muslims ask God (﷾) to bless him, in words he taught them. The Qur'an tells them to do it. Islam teaches them to pray to God (﷾) alone, never to him. He himself said: do not over-praise me; I am only a servant. When he died, Abu Bakr said that whoever worshipped Muhammad should know he was dead.
Where it lands — Muslims honour the Prophet (ﷺ) as a servant and messenger of God (﷾). Worship is for God (﷾) alone, who never dies.
Perspectives
The state teaching of 1889-1945 (State Shinto)
From 1889 to 1945 the Japanese state taught that the emperor was sacred. The commentary on its constitution called him Heaven-descended, divine and sacred. The old books trace the imperial line to Amaterasu, revered as the kami of the sun.
Ito's commentary on Article 3 of the Meiji Constitution describes the emperor. He is descended from Heaven, divine and sacred, and above all his subjects, it says.
Rebuttal
Heaven-descended or not, no man is divine. The Qur'an says every being in heaven and earth comes to God (﷾) as a servant. The Prophet (ﷺ) himself was told to say: I am but a man like you.
The Nihon Shoki traces the imperial line to Amaterasu. In one version it gives, she tells her grandchild that her descendants shall be lords of the land.
Rebuttal
Descent from heaven, even if it were so, would make no one divine. Every being in the heavens and the earth comes to God (﷾) as a servant. Nor does lineage give anyone rank before God (﷾). The Qur'an says the most honoured is the most righteous. The Prophet (ﷺ) said lineage does not hurry forward one whom his deeds hold back.
Akitsumikami means a kami in human form, not the Creator. No one taught that the emperor made the world.
Rebuttal
Islam forbids more than calling a man the Creator. Not even a prophet may tell people to worship him, or to take angels and prophets as lords. If a prophet may not, no other man may. Every being in the heavens and the earth comes to God (﷾) as a servant.
Historical: the record of 1945 and 1946
The Shinto Directive of 15 December 1945 ended state support for Shinto. It also ended its teaching in schools paid for by the state. The emperor's rescript (a formal statement) of 1 January 1946 spoke of the ties between emperor and people. They did not rest, it said, on the false conception that the Emperor is divine.
The Shinto Directive (SCAPIN-448) ended state support for Shinto. It stopped the teaching of Shinto doctrine in schools paid for by the state.
The emperor's rescript (a formal statement) of 1 January 1946 said the ties between the emperor and the people do not depend on legends and myths. Nor do they rest on the false conception that the Emperor is divine.
The Japanese word rendered "divine" is akitsumikami, "manifest kami". The rescript says nothing about descent from Amaterasu.
The Islamic perspective
No human being is divine. Every being comes to God (﷾) as a servant, and the Prophet (ﷺ) himself was told to say he was a man. Lineage gives no rank before God (﷾). Honour belongs to people and worship to God (﷾) alone. Islam's teaching rests on the Qur'an, not on any state, and it invites the reader to weigh the Qur'an and the last Prophet (ﷺ).
Every being in the heavens and the earth comes to God (﷾) as a servant. The Prophet (ﷺ) was told to say: I am but a man like you.
No one given prophethood may tell people to worship him, and the Prophet (ﷺ) forbade over-praise of himself.
When the Prophet (ﷺ) died, Abu Bakr spoke to the people. Whoever worshipped Muhammad, Muhammad is dead. Whoever worshipped Allah (﷾), Allah (﷾) is alive and never dies.
The most honoured before God (﷾) is the most righteous. And family line does not carry forward a person whose own deeds hold him back.
Honour is due to parents and elders, and worship to God (﷾) alone.
The Qur'an invites careful reading, and Muhammad (ﷺ), the last Prophet, was sent to all people.