The two readings are essentially identical, though the second is arguably more explicit in negation. Both mean that those believers will not experience fear; or that there need be no fear concerning them. *NB: Ḥamzah, like Yaʿqūb, pronounces this ʿalayhum.)
He has revealed to you ˹O Prophet˺ the Book in truth, confirming what came before it, as He revealed the Torah and the Gospel
Explanation
The two readings are essentially identical, though the second is arguably more explicit in negation. Both mean that those believers will not experience fear; or that there need be no fear concerning them. *NB: Ḥamzah, like Yaʿqūb, pronounces this ʿalayhum.)