Angels could fall but redeemed humans in eternity will not — Scripture promises 'with him forever'; the mechanisms likely include: prior choice already made, maximum Holy Spirit indwelling, perfected environment, and crucially the removal of the sin nature.

Mike reasons from the biblical promise backward to possible mechanisms: (1) we have already made our choice through temptation and rejected it; (2) maximum indwelling of the Holy Spirit has a preserving effect; (3) the environment is perfected — no surrounding wickedness; (4) most importantly, the sin nature (the flesh) is removed at glorification. 1 Corinthians 15:53: 'this corruption must put on incorruption.' Without the internal pull toward sin, there is nothing drawing one away from God.