154. Then, We gave Musa the Book [ the Tawrah], complete for that which is best, and explaining all things in detail and a guidance and a mercy that they might believe in the meeting with their Lord.
155. And this is a blessed Book (the Qur'an) which We have sent down, so follow it and have Taqwd, so that you may receive mercy.

After Allah described the Qur’an by saying,

And verily, this is My straight path, so follow it...}
He then praised the Tawrah and its Messenger,

Then, We gave Musa the Book...}

Allah often mentions the Qur’an and the Tawrah together. Allah said,

And before this was the Scripture of Musa as a guide and a mercy. And this is a confirming Book in the Arabic language .} [46:12].

Allah said in the beginning of this Surah,

Say : "Who then sent down the Book which Musa brought, a light and a guidance to mankind which you have made into paper sheets, disclosing (some of it) and concealing (much)?' 1 } (6:91), and

And this is a blessed Book which we have sent down...} [6:92]
Allah said about the idolaters,

But when the truth has come to them from Us, they say: "Why is he not given the like of what was given to Musa?”} [28:48]. Allah replied.

"Did they not disbelieve in that which was given to Musa of old?" They say: " Two kinds of magic [the Tawrah and the Qur'an], each helping the other!" And they say : "Verily, in both we are disbelievers."} [28:48]

Allah said about the Jinns that they said,

"0 our people! Verily, we have heard a Book sent down after Miisa, confirming what came before it, it guides to the truth."} [46:30]

Allah’s statement,

... complete for that which is best, and explaining all things in detail..."}

means; *We made the Book that We revealed to Musa, a complete and comprehensive Book, sufficient for what he needs to complete his Law.’ Similarly, Allah said in another Ayah,

And We wrote for him on the Tablets the lesson to be drawn from all things.} (7:145]

Allah’s statement,

fbr that which is best,} means: ‘as a reward for his doing right and obeying Our commands and orders.’ Allah said in other Ayat,

Is there any reward for good other than what is best?>[55:60],

And (remember) when the Lord of Ibrahim tried him with (certain) commands, which he fulfilled. He (Allah) said (to him), "Verily, I am going to make you an Imam for mankind."} [2:124] and,

And We made from among them (Children of Israel), leaders, giving guidance under Our command, when they were patient and believed with certainty in Our Ayat.} (32:24]

Allah said;

and explaining all things in detail and a guidance and a mercy}

praising the Book that Allah sent down to Mtisa, while,

... that they might believe in the meeting with their Lord. And this is a blessed Book (the Qur’an) which We have sent down, so follow it and have Taqwa so that you may receive mercy .4

This calls to following the Qur’an. Allah encourages His servants to follow His Book (the Qur’an) and orders them to understand it, adhere to it and call to it. He also describes it as being blessed, for those who follow and implement it in this life and the Hereafter, because it is the Firm Rope of Allah.