Tafsir of Al-An'am 6:154

{Then We gave Moses the Book, complete...}

{Then}—greater than that—is that We gave {Moses the Book, complete}, and We sent down this blessed Book.

It is said: It is a conjunction to what preceded earlier in the surah, from His saying: {And We bestowed upon him Isaac and Jacob} (Al-An'am: 84).

{Complete for the one who did good} Meaning: A completion of honor and favor upon the one who did good—upon the one who was a righteous doer of good. He intends the category of those who do good. This is supported by the reading of ‘Abdullah: {upon those who did good}.

Or, he intended by it Moses (peace be upon him), meaning: a completion of honor upon the servant who performed the obedience of conveying [the message] and everything he was commanded to do.

Or: "Complete for the one who did good" regarding knowledge and laws. One says "he did good in the thing" when he masters its knowledge; meaning: an addition to his knowledge by way of completion.

Yahya ibn Ya‘mar read: {‘ala alladhi ahsanu} (in the nominative case), meaning: "upon the one who is best," omitting the subject, like the reading of one who reads: {mathalan ma ba‘udatan} (in the nominative), meaning: upon the religion which is the best and most pleasing religion.

Or: "We gave Moses the Book, complete," meaning: perfect and whole, in the best manner that books can be, meaning: in the way and path that is best. This is the meaning of the statement of al-Kalbi: "He perfected the Book for him in its best form."

{And this is a Book We have sent down, blessed, so follow it and fear [Allah] that you may receive mercy. [Lest] you say, "The Book was only sent down to two groups before us, and we were unaware of their study." Or [lest] you say, "If only the Book had been sent down to us, we would have been better guided than them." There has now come to you a clear proof from your Lord, and guidance and mercy. Then who is more unjust than one who denies the verses of Allah and turns away from them? We will recompense those who turn away from Our verses with the worst of punishment for their having turned away.}