COMMENTARY on 4:65
A. Yusuf Ali:

Translation:
But no, by the Lord, they can have no (real) Faith, until they make you judge in all disputes between them, and find in their souls no resistance against Your decisions, but accept them with the fullest conviction. 583
Commentary:

583  The test of true Faith is not mere lip profession, but bringing all our doubts and disputes to the one in whom we profess faith. Further, when a decision is given we are not only to accept it, but find in our inmost souls no difficulty and no resistance, but on the contrary a joyful acceptance springing from the conviction of our own faith.

 

Muhammad Asad:

Translation:
But nay, by thy Sustainer! They do not [really] believe unless they make thee [O Prophet] a judge of all on which they disagree among themselves, and then find in their hearts no bar to an acceptance of thy decision and give themselves up [to it] in utter self-surrender. 84
Commentary:
84  This verse lays down in an unequivocal manner the obligation of every Muslim to submit to the ordinances, which the Prophet, under divine inspiration, promulgated with a view to exem­plifying the message of the Qur’an and enabling the believers to apply it to actual situations. These ordinances constitute what is described as the sunnah (lit., "way") of the Prophet Muhammad, and have (whenever they are authenticated beyond any possibility of doubt) full legal force side by side with the Qur’an: see verse 80 of this surah.