my brother in Christ

From my +‎ brother in Christ. (This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)

my brother in Christ (plural my brothers in Christ)

1. (Internet slang) A condescending term of address, used before a statement which intends to dispel someone's lack of self-awareness.

• Despite using the word brother, this term is often applied regardless of gender. The female equivalent my sister in Christ is occasionally used, while the gender-neutral equivalent my sibling in Christ is rarely used.

• "My Brother In Christ, You Made This A Meme", Vice, March 23, 2022