Eternal sin
Thomas Aquinas lists, or has responded to, six sins that supposedly go against the Holy Spirit:
Thomas Aquinas explains that the unforgivability of blasphemy against the Holy Spirit means that it removes the entrance to these means of salvation; however, it cannot hinder God in taking away this obstacle by way of a miracle.
Chinese views on sin
The concept of "sin; offense against god" is a long-standing hamartiological problem for Christianity in China. Uhalley and Wu (2001:71-72) described it as a "notorious crux in Christian-Confucian dialogue"; "The central issues here are the doctrines of sin as an offense against God, original sin, and redemption, which are, for Christians, revealed doctrines. But all are absent from, rather than contrary to, Confucian values."