Used to show that Peter says Jesus knows everything, including the heart, which the speaker treated as a divine attribute.
Scripture spotlight
John 21:15-17
bible
15 So when they had eaten their breakfast, Jesus said to Simon Peter, "Simon, son of Jonah, do you love me more than these?" He said to him, "Yes, Lord; you know that I have affection for you." He said to him, "Feed my lambs." 16 He said to him again a second time, "Simon, son of Jonah, do you love me?" He said to him, "Yes, Lord; you know that I have affection for you." He said to him, "Tend my sheep." 17 He said to him the third time, "Simon, son of Jonah, do you have affection for me?" Peter was grieved because he asked him the third time, "Do you have affection for me?" He said to him, "Lord, you know everything. You know that I have affection for you." Jesus said to him, "Feed my sheep.
This passage was cited because Peter says to Jesus, "You know all things," and Jesus accepts the statement, supporting the claim of Christ's omniscience.