deliver a sermon or religious address to an assembled group of people, typically in church:he preached to a large congregation [with object]:our pastor will preach the sermon (as noun preaching)large numbers of people would come to hear his preaching
[with object] publicly proclaim or teach (a religious message or belief):he preached the word of God
[with object] earnestly advocate (a belief or course of action):my parents have always preached toleration and moderation
give moral advice to someone in a pompously self-righteous way:viewers want to be entertained, not preached at
preach to the converted
advocate something to people who already share one’s convictions about its merits or importance.