I remember my dad with that towel strapped around him, kneeling down at each of the men's feet and quoting:
John 13:14-15
If I then, your Lord and Master, have washed your feet; ye also ought to wash one another's feet. For I have given you an example, that ye should do as I have done to you.
This is what Jesus said to his disciples after he washed all their feet. You can read the full account in John 13. Jesus was showing them how they should treat one another, but most importantly how none of us should think ourselves better than another or be so high that we can't kneel and wash another's feet.
Some commentators had said that Jesus didn't mean for them to do it but only to bring them to humility in my mind. I suppose that is so, but my dad chose to do it and God blessed every time! My dad would cry as he went along and so would everyone else. I remember crying because of the love in that place as my dad humbled himself to wash the dirty feet of others. Then, seeing his church members cry also as they realized how much their pastor loved them. He loved them enough to humble himself and do as the Lord Jesus had done. It was a special time and one that when I bring it to remembrance, pours the humility and love of the act all over me.
How about instead of criticizing one another, looking down on them because they aren't doing what we are doing, or have done, that we instead - wash their feet? Just thinking of washing the feet of those you criticize should bring humility in your heart and show you your own pride. If not, then maybe it is time you brought out the basin and served them.
My dad had a heart for people (and still does) and that is something they will always remember. I will leave you with Barnes' commentary on this important lesson Jesus taught:
It is the manifest design of Jesus here to inculcate a lesson of humility; to teach them by his example that they ought to condescend to the most humble offices for the benefit of others. They ought not to be proud, and vain, and unwilling to occupy a low place, but to regard themselves as the servants of each other, and as willing to befriend each other in every way. And especially as they were to be founders of the church, and to be greatly honored, he took this occasion of warning them against the dangers of ambition, and of teaching them, by an example that they could not forget, the duty of humility.