Question: Why does God demand absolute loyalty from our souls?
Answer: Darkness can’t coexist with love and light. God won’t let you choose a part of your life that you can set apart for him and then keep on doing what you want, i.e. sinning, with the rest of your life. We must give up all our heart to God because He deserves it. He gave up his entire life as a human for our sake. He feeds us with His Body and Blood; His love is absolute; He came into this world to save us. That is why He cannot say that there is a part of your heart and your life that belongs only to you and that you can dispose of as you please. You have to hand your whole life over to God and to rely on his Providence. That is how we can enter eternal life and defeat death. Ye cannot serve God and mammon (Cf. Matthew 6: 24). You can’t divide your heart and your life. You’ve got to choose yes or no. If we decide to follow Christ, we must follow him till the end. But he that shall endure unto the end, the same shall be saved (Matthew 24: 13).
The Lord’s human nature was without sin. He died for us on the Cross. He knew that He had to offer a sacrifice. The Lord took the guilt of the entire humankind because He could do so as our Creator.
Many become Orthodox in the same way: not by logic, deliberation, and research, but by the workings of the Holy Spirit that make the presence of God visible to us.
The apostle tells us: "Each of you is a temple of the Holy Spirit." Every human being is a temple. Some temples are built by people and consecrated as houses of the Lord. Other temples of God are not built by hand.
St Justin Martyr quoted God as saying, “In whatsoever things I shall take you, in these I shall judge you.” (Dialogue with Trypho, Chapter 47, cf. Matthew 24: 42).