Classical discussions give assent of the heart a foundational place in faith, while outward profession matters for recognition and legal dealings. The occurrence of a major sin does not in every case erase both of these. The inference “the person sinned, therefore the person rejected every truth of faith” does not follow.
This does not minimize sin. The existence of faith and its perfection through obedience are distinguishable. Remaining within faith does not turn wrongdoing into an acceptable act or remove accountability.