Justin Bieber better do some praying with pastor Carl Lenz on this one!

The now not-on-tour singer attended services at the Saban Theather City Church event Tuesday night and after his soul was saved, he left calmly in his HUGE new 4x4 Ford truck and even though he was pulling out of the driveway fairly slowly, he didn't realize his own size and clipped a photographer standing at the front passenger side of the truck.

The paparazzo's camera was hit by the front light and it was enough to knock the poor guy to the ground -- unfortunately, Bieber didn't realize what had happened and he kept moving forward, apparently running over the lower half of the photographer's body!

With a big truck and huge tires like that, that's GOTTA hurt! Bieber quickly exited the car and ran to the photographer's side, held his hand and -- spoke with him as Biebers' friends also gathered around. Police and emergency crews were called to the scene and the pap was taken away in an ambulance. We're told Bieber was not cited by police.

P.S. - Kourtney Kardashian turned up at church tonight because ... of course this cougar's gotta keep her claws in this young man! She wasn't counting on all the police activity; we're pretty sure she was hoping to meet up with Bieber after church but the Biebs must have been slightly distracted ...