It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: The eyes also commit adultery, the hands also commit adultery, the feet also commit adultery, and the private part either confirms or denies it.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 10829