sawthruglassclearly raises an important and unpleasant question:
"I am fairly certain that he must register as a sex offender, which should keep him out of the ministry because he has to stay away from children. Churches could risk legal ramifications if they allow him to speak, be on staff, etc."
The Chicago Tribune reported that Schaap will be registered as a sex offender for the rest of his life. One small church (in 2009) hired a convicted sex offender after he completed his parole, and there were no restrictions afterwards in him pastoring. Some states forbid sex offenders from living close to churches, but I cannot find anything on the internet about a state forbidding a sex offender to pastor after he has completed his sentence.
I found a Christian site that defended the practice claiming that if Jesus forgave him, Christians must forgive him. However, trusting him is another issue. One group claims that the congregation must be trained to accept a sex offender as member, while ignoring the fact that many people will leave the church if that happens.