The spiritual person is not different on the inside compared to the outside. The actions they do come forth from their changed being who resides within.
Whether you call this inner being the heart or the mind, it can be identified by your thoughts. Do your thoughts run to hate, but outwardly you practice kindness and love? Are your eyes drawn to lust and your mind entertains impure thoughts, but you would never act on your fantasies?
God knows your heart, your mind, and he can see your thoughts and intentions as easily as you can read these words. Easier even. He can see when your outward actions are really just a cover for the rot that resides within.
Strive for purity of mind and heart as well as purity of deed. Nothing can be hidden from your King, and nothing should be. He is the one to confess to and to seek help to improve. Seek Him in the privacy of your mind so that your heart and mind are redeemed by displacing the sin that you might find.
"Even in your thoughts, do not curse the king, nor in your bedroom curse the rich, for a bird of the air will carry your voice, or some winged creature tell the matter." - Ecclesiastes 10:20