Too many people come into music to just get quick satisfaction and leave, much like how a rapist works. This affects other other rappers who actually work hard to achieve, and cripples their faith, much like how a rape victim is disheartened by said act, and may lose faith in God.
“Rape the culture” can be expanded to mean that they utilize black culture in their tunes, but only take from it, never giving back. This is a use similar to the Rape of Africa by the Europeans during the colonial era.
The next line may imply that too many rappers lose their faith once they start being successful.