A blessing is a ritual or saying to make something or someone sacred or holy.
The word blessing is inherited from Germanic into Old English. Although it was inherited from Germanic, it is not seen in any of the other Germanic languages such as Old Norse or Old Frisian. One of the Old English spellings is blóedsian, evolving into bledsen in Early Middle English, then settling on blessed in Middle English.
Blessings are common amongst all types of religions, including witchcraft. Priests and priestesses will bless practitioners. Priests in Christian religions will often use holy water to facilitate their blessings.
Sources:
“Bless, V. (1) & Int.” Oxford English Dictionary, Oxford UP, June 2024, https://doi.org/10.1093/OED/2889565340.
Personal experience.