What is the ruling on one who masturbates, and is ghusl (ritual bath) obligatory upon him, or only wudu (ablution)?

If masturbation leads to the emission of semen, then ghusl (ritual bath) is obligatory; otherwise, it is not. If pre-seminal fluid (madhiy) is discharged, then washing the penis and whatever it touched, and performing wudu (ablution) for prayer, becomes obligatory. Abstaining from this habit is forbidden (haram) because it constitutes a transgression of what Allah has made lawful. Allah Almighty says: "And those who guard their private parts Except from their wives or those their right hands possess, for indeed, they are not to be blamed But whoever seeks beyond that, then those are the transgressors." A Muslim must repent and avoid this habit.