Does saying "it's fine" with one's heart or tongue about a forbidden act, and then repenting from it, constitute an act of making it permissible (istihlal) or a form of negligence, and does it necessitate Ghusl?

"A piece of advice for those afflicted by obsessive doubts (waswas) is to completely disregard them and not get carried away with Satan. Ibn Taymiyyah holds that waswas affects everyone who turns to Allah through remembrance, because Satan is a highway robber. The questioner is also advised not to dwell on the aforementioned phrase, to close this door, and to occupy oneself with what is beneficial in matters of religion and worldly life."