They have certainly disbelieved who say, "Allah is the third of three." (5:73)

﴿لَّقَدْ كَفَرَ الَّذِينَ قَالُوا إِنَّ اللَّهَ ثَالِثُ ثَلَاثَةٍ ۘ وَمَا مِنْ إِلَٰهٍ إِلَّا إِلَٰهٌ وَاحِدٌ ۚ وَإِن لَّمْ يَنتَهُوا عَمَّا يَقُولُونَ لَيَمَسَّنَّ الَّذِينَ كَفَرُوا مِنْهُمْ عَذَابٌ أَلِيمٌ﴾
[ المائدة: 73]

5:73 They have certainly disbelieved who say, "Allah is the third of three." And there is no god except one God. And if they do not desist from what they are saying, there will surely afflict the disbelievers among them a painful punishment.

The Christians who say that ‘Allah is part of the Trinity: Father, Son and Holy Spirit’ have committed disbelief.
Allah is far above such a statement.
Allah is not many, but He is only One God Who has no partner.
If they do not stop saying such things, a painful punishment will afflict them.

Surely, disbelievers are those who said: "Allah is the third of the three (in a Trinity)." But there is no ilah (god) (none who has the right to be worshipped) but One Ilah (God -Allah). And if they cease not from what they say, verily, a painful torment will befall the disbelievers among them.

phonetic Transliteration

Laqad kafara allatheena qaloo inna Allaha thalithu thalathatin wama min ilahin illa ilahun wahidun wain lam yantahoo AAamma yaqooloona layamassanna allatheena kafaroo minhum AAathabun aleemun

Abdullah Yusuf Ali - Translation

They do blaspheme who say: Allah is one of three in a Trinity: for there is no god except One Allah. If they desist not from their word (of blasphemy), verily a grievous penalty will befall the blasphemers among them.

Safi-ur-Rahman al-Mubarakpuri

Surely, they have disbelieved who say: "Allah is the third of three." And there is no god but One God (Allah). And if they cease not from what they say, verily, a painful torment will befall on the disbelievers among them.

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