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.
Christian perfection
Wesley did not, however, believe in an absolute "sinless" perfection, and he repudiated those who taught that Christians could achieve such a state. Wesley defined sin as conscious, voluntary transgression of known divine law. Involuntary transgressions (such as those arising from ignorance, error, and evil tempers), according to Wesley, were not properly called sins. Therefore, regenerated Christians would continue to be guilty of involuntary transgressions and would need to practice regular confession. Furthermore, Christians continued to face temptation, and Wesley acknowledged that it was possible for a regenerated Christian to commit voluntary sin (if, in the words of Noble, the Christian ceased "actively trusting in God through Christ and living in the divine presence"), which would also necessitate confession of sin.