I have a question.

Must a person repent of a known sin to be forgiven of that sin?

The person claims Christ as savior.

They are baptized, attend church, pray and claim to be a Christian.

They are aware of the sin in their lives, lets say ongoing theft, but they believe God will forgive them of this sin.  They do not change and they do not pray for forgiveness of this sin.  They have justified this theft as something they must do for their job.  They give a portion of the money to charity.

Are they forgiven of the sin?  Will they be covered by the blood and accepted into heaven even though they never repented of this sin?

Looking for peoples opinions on this with or without verses, but if you have biblical support please provide it.