John 15:3
“Now you are clean through the word which I have spoken unto you.”
Do you see how He introduces Himself as tending the branches? “I have cleansed you,” He says; yet above He declares that the Father does this. But there is no separation between the Father and the Son. “And now your part also must be performed.” Then to show that He did not this as needing their ministry, but for their advancement, He adds,
Source: Homilies on the Gospel of John (New Advent)