It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The (lustful) glance is one of the poisoned arrows of Iblis. Whoever abandons it out of fear of Me, I will give him in exchange a faith whose sweetness he will find in his heart."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10324