As for those whom We have given the Scripture before (and who understand that this Qur'an is a Divine Revelation like the ones before it) come to believe in this one as well
Those who have received the previous scriptures will believe in this Qur’an. [As a matter of fact, the teachings of Qur’an are the same of the previous scriptures, before being tampered with.]
Faridul Haque
Those to whom We gave the Book before it, accept faith in it. (Some scholars among Jews / Christians)
Hasan Al-Fatih Qaribullah
Those to whom We gave the Book before, believe in it