Praising the Qur'an; the Command to Refer to the Qur'an for Judgment
Allah mentioned the Tawrah that He sent down to His Prophet Musa, the one whom He spoke directly to, praising it, commanding that it should be implemented, before it was abrogated. Allah then mentioned the Injil, praised it and commanded its people to adhere to it and follow it, as we stated. He next mentioned the Glorious Qur'an that He sent down to His honorable servant and Messenger. Allah said,
وَأَنزَلْنَآ إِلَيْكَ الْكِتَـبَ بِالْحَقِّ
(And We have sent down to you the Book in truth...) meaning, with the truth that, no doubt, is coming from Allah,
In the fifth (48) and the sixth (49) verse, the address is to the Holy Prophet ﷺ saying that to him Allah has revealed the Qur'an which confirms the Torah and Injil, Books previous to it, and is their custodian as well. This is because, after the people of the Torah altered the Torah and the people of Injil made changes in the Injil, it was the Qur'an alone which turned out to be the kind of overseer and protector which exposed the alterations made by them, lit up truth and reality in their proper perspective. Even today, the true teachings of the Torah and Injil still survive through the Qur'an while those who inherited them and those who claim to follow them have disfigured them to the extent that it has become impossible to distinguish truth from untruth. Towards the end of the verse, the Holy Prophet g has been given the same instruction as was given to the people of the Torah and the people of the Injil, that is, all orders and judgments given by him should be according to injunctions revealed by Allah, and that he should see through the ploy of these people who intend to have him decide matters according to their wishes and take his guard against their evil plans. There was a particular reason for saying what was said. Some Jewish religious scholars came to the Holy Prophet ﷺ . They told him that they were religious leaders among the Jews. If they became Muslims, the rest of them would become Muslims too. But, there was a condition to it. They said that they had a legal dispute with his people. They would bring that case to him. If, in this case, he were to decide in their favour, they would embrace Islam. Thereupon, Al-mighty Allah gave him the word of caution that he should never decide against considerations of equity and justice and the Law revealed by Allah because of the offer to become Muslims made by these people - a proposition which was not for him to worry about.
The Jews had formulated a new self-made religion by mingling their own innovations with the true religion of God. Their self interests were linked with this self-devised religion. Therefore, they were not at all ready to give it up and adopt the pure religion introduced by the Prophet. Instead of bowing down before the Truth, they took to harassing the flag-bearer of Truth, so that he should kneel down before them, give up the true religion of God and accept the religion devised by them. Had it been the will of God, He could have tied the hands of these transgressors at the very first instance and they would not have succeeded in harassing him. But God allowed them some respite to put their evil plans into action. This was done so as to make it abundantly clear that these claimants of so-called righteousness were the worst type of irreligious people; being devotees not of God but of their own self-interests. This act of God, though it constituted a hard test for the missionary of Truth, was the only way a decision might be reached as to who deserved paradise and who deserved hell. It is the weakness of the human being that he wants to fulfill his desires. Being governed by God’s commandments is, therefore, not tolerable to him. He then goes so far as to use self-devised interpretations of the Divine religion to make it conform to his desires. Pure religion is acceptable only to those who do not view things in the light of their desires, preferring to make the moral choice of rising above them. The word of God is undoubtedly the truest word. But in this present world of trial, every Truth is hidden behind the curtain of doubt. It is the test of a man that he should be able to tear asunder this curtain, that he should be able to make the unseen observable to himself, so that he may be in possession of the Truth. One who is caught up in outward doubts is a failure and one who brushes aside the veil of apparent doubts and finds the Truth has achieved success.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.