All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The door of repentance is open, praise be to Allaah, for every person whatever great his sins are, as long as the sun does not rise from the west, and as long as one's soul does not reach his throat (at the time of death). Allaah has promised to change the sins into good deeds of those who repent believe and do good deeds after having committed grave major sins, like Shirk (associating partners with Allaah), killing, and Zina (fornication or adultery). Therefore, a sinner should be keen on fulfilling the conditions of a sincere repentance, like repenting from previous sins, not committing the sins again out of fear of Allaah, bearing in mind His Greatness and seeking His Pleasure, being truly determined not to return to them again, giving back the rights to its owners, and getting rid of ill-gotten money like gambling.
For more benefit on the conditions of sincere repentance, please refer to Fatwa 86527.
We also clarified in Fataawa 83706 and 92178 that a person is held accountable for his deeds only when he reaches puberty, but if one has unjustly taken people's money, he should give them back [even if he wronged the people before the age of puberty]. We also clarified in Fatwa 89762 that stolen money should be given back to its owners if possible, and if one cannot find them, he should give the money in charity while intending the reward for them.
With regard to whoever committed Zina during the day of Ramadan, he should make up this day and expiate for breaking the fast, which is to fast two consecutive months because now there are no slaves to free. In case one is not able to fast two consecutive months, he should feed 60 poor persons. For more benefit in this regard, please refer to Fatwa 89541.
Allaah Knows best.