Luke 22:55-57

Luke’s account is essentially the same as Matthew’s and Mark’s. Peter evidently joined the circle of people seated around the fire. He first denied acquaintance with Jesus.

"Peter’s response is called a denial. The word ’deny’ (arneomai, Luke 22:57) is used in the NT as the polar opposite of the word ’confess’ (homologeo). We are to confess (i.e., acknowledge) Christ but deny ourselves (i.e., disown our private interests for the sake of Christ; cf. comment on Luke 9:23). Peter here does the reverse. He denies Christ in order to serve his own interests." [Note: Liefeld, "Luke," p. 1035.]