“We have this hope as an anchor for the soul, firm and secure. It enters the inner sanctuary behind the curtain, where Jesus, who went before us, has entered on our behalf. He has become a high priest forever, in the order of Melchizedek.” (Hebrews 6:19-20)
During the first century AD the anchor was a common symbol used by Christians. The cross was commonly adopted as a symbol around 400 AD. The anchor symbol is found in first, second and third century catacombs and cemeteries.
The anchor was a key Christian symbol during Roman persecution. Some scholars attribute the anchor symbols use to a word play in Greek—ankura resembling en kurio, or “in the Lord.” The anchor symbol used a cross member, referred to as a “stock”. Displaying this anchor was a way to discretely display a cross during times of persecution.