How about BAPTISM by sprinkling?
I read that it started in Antioch. There was a severe drought, with water rationing. There was NO bathing, etc. etc. New converts could not be immersed, but they wanted to use some water, so they began just sprinkling. Dr. Jeffrey Seif sites sources for this, in his book "To the Ends of the Earth". It could have been seen as a continuation of the sprinkling with the ashes of the red heifer - for cleansing.
Numbers 19:18 "A clean person shall take hyssop and dip it in the water (which contained some ashes of the red heifer), sprinkle it on the tent, on all the vessels, on the persons who were there, or on the one who touched a bone, the slain, the dead, or a grave."
Hebrews 10:22 "let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience and our bodies washed with pure water."