In Psalm 103, David calls upon his soul to
bless the Lord and to "forget not all his
benefits,"

Then he says, "Who forgiveth all thine
iniquities (sins), who healeth all thy diseases."

The only way God can forgive sin is through
the Atonement of Jesus. He heals diseases
the same way. The only way God can save
any part of man is by the Atonement.