Before and after situation for Paul.
If God had mercy on Paul, no one is beyond God's mercy. Paul was acting out of ignorance before.

Much of ministry is built on trust. Paul praises God for salvation

Timothy should cultivate the right personal traits. A sense of right and wrong is important; a work of the Holy Spirit. There also hanging on to what we believe.

Christian writers don't describe heresy in too much detail. Conscience informed by faith can steer us though dilemmas.
Strive to advance God's kingdom.