Hi! I’m not surprised that you continue to look through the lens of Sola Scriptura since you’ve been immersed in that mindset but not sure why you continue to do so? You’ve not defended it?
The Sign of the Cross is the movement of the right hand from the forehead to the chest and then left and right upon the shoulders. It can also be made in the air without touching the person. It is often used as a form of prayer.
I really can not give you scripture in my answer because the sign of the cross is unsupported by Scripture. It is not mentioned nor seen in scripture anywhere.
I do know that Catholics find support for the sign of the cross primarily in their many years of church tradition and, in Exodus 17:9-14 and Revelation 7:3; 9:4; 14:1. While the passages do speak of a sign on the forehead for protection from God’s judgment, the verse must be interpreted in light of their context. So when we do that there is no reason to believe any of the verses are plainly talking about the Sign of the Cross.
So the sign of the cross is not biblical and it is by no means required of Christians because it is not instructed by the Word of God.
“The writings of the Fathers, as authentic witnesses to the apostolic teaching in the early Church, are replete with references to the Sign of the Cross….There has never been a time in the flow of historic Christianity that the Sign of the Cross has not been devoutly practiced. Only recently, since the Reformation, has the Sign of the Cross (along with the Crucifix, holy water and other visible signs) been rejected as idolatrous by many Protestant traditions. However, even Martin Luther in his Taufbuechlein retained the Sign of the Cross in the baptismal service and used the Sign of the Cross as one of his last gestures before death.”
Wide Spread Interests 