Genesis 3:15 says that Satan will bruise the heel of the Savior, but the Savior will crush the head of Satan. Ancient crucifixion involved driving a nail through the top of one’s foot and out through the heel. Hence, the prophecy was fulfilled as Christ completed the Atonement, bruising His own heel in the process but ultimately crushing the head or whole being of Satan. How can we be like unto the bruised (imperfect) heel of the Savior that crushes the head of the enemy?
The two criminals who hung beside the Redeemer died of suffocation after a few days (their legs were broken, as was custom if they could survive for that long). Jesus, however, died after only six hours- literally of a broken heart. It is a very rare medical condition (tatksubo cardiomyopathy) caused by an extreme rush of stress of adrenaline. When this happens, the heart muscle is ruptured, making blood and a clear liquid spill out. Sure enough, when a spear pierced His dead body, blood and a water-like fluid spilled out of Christ. No wonder that Jesus asks us to come to Him with a broken heart. Three parts of being a disciple involve baptism (water), repentance (broken heart/blood), and the Holy Ghost (spirit). These three things left the body of the Redeemer on that day. How can we metaphorically die on our cross every day?
The Lord is nigh unto them that are of a broken heart; and saveth such as be of a contrite spirit.