This water prefigured immersion [into Christ], which now also saves you, not by removing dirt from the [physical] body, but [by serving] as an appeal [or, “pledge”] to God for a clear conscience through the raising of Jesus Christ from the dead.
we should draw close [to God] with a sincere heart and a fully assured faith, having had our hearts sprinkled from a guilty conscience [See 9:13-14] and having had our bodies washed with clean water [i.e., in our immersion].
So, when Pilate saw that he was not convincing anyone, but that a riot was brewing instead, he took water and washed his hands in front of the crowd saying, “I am not responsible for this man’s blood. [Note: Some ancient manuscripts say “righteous man’s blood”]. You tend to the matter.”
Peter said to Him, “[No], you will never wash my feet.” Jesus replied to him, “If I do not wash you, you will not be able to participate with me [i.e., as a disciple].”
Jesus replied to him, “The person who has already had a bath is completely clean and does not need to wash anything but his feet. And you disciples are [already] clean [i.e., spiritually], but not every one of you.”