Reference to His blood? Been cleansed by it, only need to wash feet because it takes us to evil places in this world...feet getting dirty; Moses taking off his shoes on HOLY ground (the very near presence of God) Once we have been cleansed by JESUS, it's once for all time, don't need to worry about losing our salvation; (He is the author and finisher of our faith) just need to focus and put energy into dealing with current sin