Quran 7:143:


And when Moses arrived at Our appointed time and his Lord spoke to him, he said, “My Lord, show me [Yourself] that I may look at You.” [Allah] said, “You will not see Me, but look at the mountain; if it should remain in place, then you will see Me.” But when his Lord appeared to the mountain, He rendered it level, and Moses fell unconscious. And when he awoke, he said, “Exalted are You! I have repented to You, and I am the first of the believers.”

The following excerpt is taken from the “Study Quran” under the commentary of the above verse:

This verse speaks directly to the issue of the human ability or inability to “see” God and seems to support the view that God cannot be seen by human beings, at least in the ordinary sense of seeing, in this world. It is consistent with the statement in 6:103: Sight comprehends Him not, but He comprehends all sight. Moses’ desire to see God is engendered by the state of intimacy he experienced with Him upon the mountain. There his Lord spoke unto him without intermediary (Ṭs, Z); and, according to a legendary report, God was so close that Moses could hear the scratching of the pen across the tablets as they were being written upon by God (Ṭ). With this closeness and the sweetness of God’s speaking to him (Su), Moses was overcome with spiritual ecstasy (Qu), yearned to be yet nearer to God, and was emboldened to ask, My Lord, show me, that I might look upon Thee (Ṭ). Some argued that Moses, who surely knew that God transcended all form and corporeality and thus could not be seen physically, asks this only to satisfy the Israelites, who in 2:55 declare, O Moses, we will not believe thee till we see God openly (Ṭs, Z). Still others suggest that Moses was not asking for a physical vision, but rather for such complete spiritual knowledge (maʿrifah) of God that it would be as if he were able to see Him directly (Ṭs, Z). The verb show me might also be translated “cause me to see”—that is, “grant me the ability to see”—so that Moses might look upon God and attain the vision he desires. Some commentators understand God’s response, Thou shalt not see Me, to mean that God is not seen in this world, but may be in the next (IK, Ṭ), sometimes invoking 75:23, which
speaks of the righteous gazing upon their Lord in the Hereafter; and Sufi writers speak of the ability to see God inwardly, with the eye of the heart. Others, however, argue that the response Thou shalt not see Me is stated in an emphatic form, indicating that God will not be seen, even in the next world (Ṭs, Z). In the Biblical account, Moses is told that none can see the Face of God “and live” (Exodus 33:20), and some commentators mention this as well (IK, Ṭ) or note that, had Moses not looked at the mountain when God manifested Himself, he would have died (Su). According to one report, Moses responded that he would rather see God and die than live without seeing Him (Ṭ). For Sufis, this may be connected with the idea that the vision of God in this life is only possible after the “death of the ego,” when one has completely “died” to the passions and desires of the soul. The annihilating power of God’s Self-Manifestation is similarly suggested in the saying attributed to the Prophet, “His veil is light. Were He to remove it, the Glory of His Face would burn up everything His Sight reached” (Su). That the mountain crumbles after God says of it, if it remains firm in its place, then thou wilt see Me, indicates that seeing God with the physical eye is as impossible as the mountain being able to withstand God’s Self-Manifestation (Z); it demonstrates the annihilating power of that vision, since even the mountain, so much larger and stronger than Moses himself, was incapable of bearing it (IK). He made it crumble to dust might also be translated “He leveled it to the ground.” Elsewhere, mountains are awed or moved by the Power of God; see, for example, 33:72, where the mountains fear accepting the Trust of God, and 19:90–91, where it is said that the earth would be rent asunder and the mountains destroyed by the claim that God has a son. Moses fell down in a swoon out of sheer awe (Z) or as the result of being passed over by one of the angels (Ṭ, Z). In a swoon translates ṣaʿiqa, which might also be translated “thunderstruck,” from the same root as the thunderbolt (ṣāʿiqah) that is said to have struck the Israelites for asking a similar question in 2:55. Some indicate that Moses actually died in this moment and was brought back to life (Qm, Ṭ, Z), although others argue that recovered (afāqa) connotes arousal from a state of unconsciousness, rather than from physical death. Upon recovering, Moses “turns in repentance,” repenting of having asked to see God (Ṭ, Ṭs, Z). Moses’ assertion that he is the first of believers may mean that he was the first among the Israelites of his time to believe (Ṭ), that he was the first to believe that God could not be seen physically (IK, Qm, Ṭs, Z), or that he was the foremost believer of his time. The Sufi tradition speaks of those who seek, and sometimes receive, the blessing of “seeing,” or “witnessing” God, or receiving an inward vision of God. Al-Sulamī, commenting on this verse, indicates that “nothing can withstand the witnessing of God save the hearts of the gnostics,” which God has adorned with spiritual knowledge of Himself and illuminated with His Light. Even so, al-Sulamī indicates that this “witnessing” really describes God’s witnessing or seeing Himself, “for the Real is witnessed by none but Himself.”