The earliest Crucifixes (they were not ashamed to put Jesus on the cross, they used the full Crucifix), Had a skull and crossbones at the base of the cross. Ancient peoples believed that Golgotha was the place where the bones of Adam were buried. So when depicting the cross of Christ, they placed the God of Love upon the cross with the bones of "the first Adam" as Paul calls him. at its base.
The precious blood of our Savior dripped down upon the bones of Adam and redeemed him to God. O God on this Passion Friday, Cleanse us by your precious and Holy blood. Redeem us fully, in every area of our lives, right to our very bones.