What is the reward for the chaste person in this world and the Hereafter, what is the punishment for the fornicator in this world and the Hereafter, and are the chaste person and the repentant fornicator equal?

The reward for one who abstains from the forbidden in this world is that Allah will make him chaste, just as he made himself chaste, based on the Prophet's (peace be upon him) saying: "And whoever seeks chastity, Allah will make him chaste." As for the Hereafter, he is promised success, as stated in Surat Al-Mu'minoon. As for the fornicator, he has committed a grave sin for which Allah has threatened punishment. However, if he repents with sincere repentance, then he is like one who has no sin. His sin may also bequeath him humility and brokenness, which makes him more cautious and apprehensive in his journey towards his Lord.