As a Servant, it was our Lord's deepest desire to present us to the Father faultless, perfected, and clean. He, therefore, was our Savior through His sacrifice - that is, the blood He shed for us that washed away our sins and the condemnation they brought. By washing His disciples' feet, He was giving them an example of the ministry they would receive. They, too, would lay down their lives in order to present every man faultless, perfected, and clean to the Father, that we might be received into the family of God with joy.
The disciples would learn to lay down their lives and their rights for others, just as Jesus had done for them; and that is the unmistakable Spirit of all true ministry. No servant of God serves himself at the expense of the the church, but he can be found washing feet, serving the poor, aiding widows and orphans, and preaching the unadorned Gospel of Jesus Christ. We who are true servants desire to see God bring many sons and daughters to glory; and we are given the honor of washing their feet, so they might sit at the Lord's table, just as Jesus did for us. This is what Jesus was teaching His disciples by washing their feet, and this is what He is teaching us - ". . . you will know after this." Now you know.
Let's Pray - Dear Lord, thank you for teaching us the value of service. May we do the same for others that You have done for us. May You find us washing our brothers' and sisters' feet. In Jesus, amen.