In the Old Testament law, because of man’s hardness of heart, it was possible for a man to put away his wife for trivial reasons. When men and women become bitter, every trivial thing rises to intolerable proportions, and the thing cannot be resolved. But when a woman was put away by a man for trivial reasons, it was required that he give her a bill of divorce, so that she could prove she was no longer bound to such a man.
When we drift away from God, and are unfaithful to Him, we sometimes assume that a divorce has happened because that is what we deserve. But God does not treat us according to our merits, which are actually demerits, but rather in accordance with the obedience of His Son, Jesus Christ.
So when say that we are separated from God, He often surprises by asking us to prove it. We are emotionally estranged from Him, on our side of things, but He asks us to prove that He divorced us. “Where is the bill of divorce?” the Lord asks in Isaiah 50:1. Your sins have separated you, but do not pretend that He has acted the part of an irritable husband.
So if you are a Christian who feels distant from God, all you must do is surrender that distance—you are the one who embraced it—repent of it, and come, return. So come, and welcome, to Jesus Christ.