Holier-than-thou
WIKIMEDIA DISAMBIGUATION PAGE
Holier Than Thou; Holier-than-thou attitude; Holier than thou attitude; Holier than thou; Holier-than-thou (disambiguation)
A "holier-than-thou" attitude is a form of self-righteousness. The phrase originates from Isaiah 65:5 in the King James Bible, which says (spelling modernized): “Stand by thyself, come not near to me; for I am holier than thou”