That happened all the time in the Bible.
Heck, God HAD to used flawed individuals to do His work,
because He only had one Son, and everyone else is wicked.
Everyone may be wicked inasmuch as everyone is a sinner. But I think God is able to draw a distinction between a tight-fisted old fart like me who doesn’t tithe and a miserable wretch like Dr. Tiller who kills babies for profit.