﴿ وَٱلَّذِىٓ أَوْحَيْنَآ إِلَيْكَ مِنَ ٱلْكِتَٰبِ هُوَ ٱلْحَقُّ مُصَدِّقًۭا لِّمَا بَيْنَ يَدَيْهِ ۗ إِنَّ ٱللَّهَ بِعِبَادِهِۦ لَخَبِيرٌۢ بَصِيرٌۭ ﴾

“And [know that] all of the divine writ with which We have inspired thee is the very truth, confirming the truth of whatever there still remains of earlier revelations for, behold, of [the needs of] His servants God is fully aware, all-seeing.”

(As for that which We inspire in thee) as for that with which We send Gabriel to you (of the Scripture) i.e. the Qur'an, (it is the Truth confirming) Allah's divine Oneness and also agrees with some laws (that which was (revealed) before it) of earlier Scriptures. (Lo! Allah is indeed Observer) He is aware of those who believe and those who do not, (Seer of his slaves) He sees their works.