Jesus knew that the Father had put all things under his power, and that he had come from God and was returning to God; so he got up from the meal, took off his outer clothing, and wrapped a towel around his waist. After that, he poured water into a basin and began to wash his disciples’ feet, drying them with the towel that was wrapped around him.
To get the full impact on what was going on, you can click the link and read the entire passage of our Lord washing his disciples’ feet on the eve of his crucifixion. What occurs is remarkable, but easily lost to us who maybe have read it time and again. Jesus took off his outer garment and embraced the attitude of a slave. In love, as the passage says, he washes his disciples as any servant or lowly slave would do.
Peter objects, thinking it is demeaning to Jesus, and definitely won’t let Jesus touch his feet. But Jesus in his kind response makes it clear that if Peter doesn’t receive this, then he has no part with Jesus. I have often heard this applied to the truth that we’re cleansed of our sin or forgiven once for all, but that this applies to the daily cleansing we need through Christ’s blood, and with confession, as well as for unknown sins, as we walk in the light (1 John). I tend to think we can make an application that way. After all, Jesus told Peter that he didn’t need any more than foot washing since he was already clean along with the other disciples (except Judas Iscariot). Later that evening he tells them that they are clean through the word he had spoken to them (John 15:3).
What I think Jesus was getting primarily at is brought out in the text (again, the full link above). If they were going to be his followers, they would have to do what he did. Take the path of humility in love to serve others, especially each other. But also others. I am a bit skeptical over whether foot washing should be an ordinance in the church, except that in such cases it can serve as a reminder of what our Lord was getting at in this passage.
Out of love, the same love of God in Jesus, we’re to reach out to each other, even in our weakness, and in humility serve one another. It is something we do, no less. We don’t wait until somehow what’s needed is in ourselves. We live in God’s love in Jesus, whether or not we feel it, whatever our experience. And we’re to take the lowly attitude of a servant in doing so. Paul expresses what our Lord was getting at wonderfully well in Philippians 2, Jesus taking on himself the form of a slave in becoming one of us in the Incarnation, and further to the very depths in his death on the cross. And how we’re to have that same mindset in our relationship to each other. This is the posture we’re to take no matter what, come what may, in and through Jesus.