Is the adulterer of a malicious nature, and how can one reconcile the entry into Paradise of everyone who dies as a Muslim with the exclusion of the malicious from it, and what is the correct way to invite sinners [to repentance]?

Adultery is one of the most heinous sins, and the adulterer has a depraved soul. However, as for one who dies as a believer and an adulterer, their matter is with Allah. If He wills, He will punish them, and if He wills, He will forgive them. One who repents from adultery with a sincere repentance is purified, for repentance erases what came before it. A believer should have mercy on sinners and hope for their guidance, detesting the sin, not the sinner, and upholding Allah's command concerning them with mercy, not harshness.