We are given the great privilege again of ascending in to the holy of holies, into the very presence of God in His holy temple, not made with human hands, but made of humans, saints, you and me, the living stones of His temple in which He dwells. As we do so, I charge you in the name of Jesus Christ to take care. We are walking into the temple of God and so, metaphorically speaking, we should take off our shoes. If we do not, we will likely track in all sorts of uncleanness.
This is what it means to confess your sins as you enter here now. It means to put away, to take off, to remove your transgressions. Put away your sin, confess your disobedience. Anger, lust, envy, backbiting, private ambition, all must go. Take off your shoes. In a short time, you will dine with these brothers and sisters – make sure you have not come to spoil the meal.
The metaphor can be adapted many ways. Wipe your feet, take off your shoes, consider where you have been walking, look down for a moment, in all humility. We are coming to worship God the Father. The Lord Jesus washed the feet of His first disciples. So let Him wash yours.