If a person commits a lot of sin and even murder but they die because of their faith and proclaim Jesus's name before dying, do they go to heaven?
The fact that the person is willing to die for the name of Christ, is a sign of his repentance. Thus, if he is martyred for the name of Christ, he will go to heaven no matter what. Repentance is critical. Faith alone is insufficient. If any person repented in his last breath, he will be forgiven, like Demas, the thief on the right who died alongside with the Lord Jesus Christ. Having faith in God and proclaiming the holy name of the Lord Jesus Christ means that you believe His teachings, which include faith, repentance, kindness, compassion, mercy, and the Holy Mysteries (sacraments). Thus, faith and deeds go hand in hand.