The Messenger of Allah (s.a.w) once asked his Companions:
''Do you feel ashamed before Allah in the fullest sense?'' The Companions replied ''Praise be to Allah, we certainly feel ashamed before Allah.'' The Prophet (s.a.w.) said. ''I do not mean your bashfulness towards Allah in a general sense. I mean your special attention to that. The man who truly feels ashamed before Allah should take care that the forces connected with his brain - his memory, his conscience, his eyes, his nose, his tongue etc- are kept far removed from an evil path. He should take care to protect his stomach from the evil forces connected with it. He should protect himself from haram earnings and haram sexual gratification. Moreover he should protect himself against the charm and glamour of this world, and remain aloof from its luxuries.
The man who can do these things fully and faithfully is the man who can be said to have felt truly ashamed before Allah.''
(Tirmidhi)