The council members clearly understood what Jesus meant in 22:69. They expected the Christ to be the Son of God and have a unique father-son relationship with God (see study notes on 1:32–33; 4:41; compare 2 Samuel 7:14; Psalms 2:7; 89:26). The Sanhedrin accused Jesus of claiming to be the Christ (compare study notes on Mark 14:62, 63–64).
You say that I am: This was a qualified affirmation, meaning that Jesus partly agreed with their statement. He probably meant, “What you say is true, but you do not understand what ‘Christ’ means.” The council understood this as a confirmation (Luke 22:71).