In the healing of the paralytic (Matthew 9:1-8; Mark 2:1-12; Luke 5:17-26), the physician Luke uses a medical term, "palsied" (KJV), the technical Greek word used to describe paralysis from disease in some part of the nervous system. Because his disease was so debilitating, the man needed comfort and healing. Jesus thus refers to him as "son," or more literally, "child," showing His fatherly compassion.
Paralysis represents sin's crippling power and the sinner's sheer helplessness to do anything to relieve his own suffering. The apostle Paul speaks of our initial lack of spiritual strength in Romans 5:6, "For when we were still without strength, in due time Christ died for the ungodly." With this miracle, Jesus forgave the penalty that the man had incurred through sin and raised him from his miserable state.
Martin G. Collins
The Miracles of Jesus Christ: Healing a Paralytic (Part Two)
Other Forerunner Commentary entries containing Matthew 9:5: