It is narrated from Sayyiduna Abu Umamah (may Allah be pleased with him) that a young man came to the Messenger of Allah (peace and blessings be upon him) and said: "O Messenger of Allah, give me permission to commit fornication." The people shouted (at this) and said: "Stop!" The Messenger of Allah (peace and blessings be upon him) said: "Leave him. (O young man,) come close." He came close and sat in front of the Messenger of Allah (peace and blessings be upon him), and the Messenger of Allah (peace and blessings be upon him) said to him: "Would you like it for your mother?" He said: "No." He said: "Likewise, people do not like it for their mothers. Would you like it for your daughter?" He said: "No." He said: "Likewise, people do not like it for their daughters. Would you like it for your sister?" He said: "No." He said: "Likewise, people do not like it for their sisters. Would you like it for your paternal aunt?" He said: "No." He said: "Likewise, people do not like it for their paternal aunts. Would you like it for your maternal aunt?" He said: "No." He said: "Likewise, people do not like it for their maternal aunts." Then the Messenger of Allah (peace and blessings be upon him) placed his blessed hand on his chest and said: "O Allah, forgive his sin, purify his heart, and guard his chastity."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7648