Assalamu Aleikum. I read a hadith in Sahih Bukhari 6573 (Vol. 8, Book 76, Hadith 577) and there it says: "Allah will come to them in a shape other than they know and will say, 'I am your Lord.'" I was wondering about the expression "other than they know". Can you explain?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

The Hadith, whose meanings are confusing to you, is related to the believers seeing Allah Almighty on the Day of Resurrection. This Hadith is authentic; it was reported by Al-Bukhari, Muslim, and others. Al-Qurtubi  said in Al-Mufhim Sharh Sahih Muslim, commenting on what confused the questioner:

“And his [Prophet’s] saying: ‘Allah would then come to them in a form other than His own Form recognizable to them’; this is a formidable place in which Allah Almighty tests His Servants to distinguish the true believer from those who deny the truth because when the hypocrites and those who show off claimed to be among the believers and the sincere, claiming that they are one of them, and that they did the same deeds as theirs and knew Allah like their knowledge, Allah tested them by coming to them in a tremendous way. He said to everyone: ‘I am your Lord.’ So, the believers denied that by saying, ‘We take refuge with Allah from you.’ Because they have already known Allah Almighty and that He is above the attributes of this image, as its features is one of a newly invented creature). That is why it is said in the Hadith narrated by Abu Sa’eed: “They say, “We seek refuge in Allah from you; we do not associate anything with Allah; they repeated this twice or thrice.” [End of quote]

This Hadith is one of the Hadiths about the Attributes of Allah, and it is known to the scholars that the Hadiths about the Attributes of Allah must be believed literally without changing words from their true context while believing that Allah is High above without resembling His Attributes with the attributes of His Creatures. The rule of the righteous predecessors regarding the Attributes of Allah is to believe in them without resembling them with the attributes of His Creatures. Shaykh al-Islam, may Allaah said in the book (Al-‘Aqeedah Al-Wasitiyyah): “As part of believing in Allah is the belief in what He described Himself with in His Book and in what His Messenger Muhammad (may Allah bless him and grant him peace) described him with, which is to affirm all the Divine Names and Attributes of Allah in a manner that suits His Majesty and Highness, without distorting their wordings or meanings, nor denying, asking how, or drawing resemblance between Allah and any of His Creation.” [End of quote]

For more benefit that Allah changes His image on the Day of Resurrection, please refer to Fatwa 360025.

For more benefit on the Attributes of Allah that there is nothing like unto Him, please refer to Fatawa 384256, 39560 and 27577.

For more benefit on interpreting the Names and Attributes of Allah, please refer to Fatawa 88618 and 92457.

Allah knows best.