Will God reward the man who patiently endured hardship so as not to commit fornication, a reward for his patience, in comparison to the man who committed fornication and then repented?

Whoever refrains from disobeying Allah, seeking His countenance, such as abstaining from adultery, Allah will reward him for this righteous deed. Indeed, it is stated in the Hadith Qudsi: "And if he abstains from it for My sake, then record it for him as a good deed." And refraining from disobedience is better. Allah has praised those who avoid grave sins and immoralities, and promised them that what is with Him is better and more enduring, and that avoiding grave sins expiates evil deeds and leads to Paradise.