Are you thinking the bullet was shot from an airplane?
If you fire a gun and shoot the bullet up into the air, from the ground, the bullet will go up until it loses speed, then it will start it's descent and fall back down.
That means the bullet is now falling down with less velocity than if it had been fired straight at the church. I don't believe it can go through shingles, plywood, and insulation and still have enough velocity to kill someone by penetrating the skull.