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. (John 13:14)

In the days of the apostles it was considered hospitable to wash a guest's feet, since most people wore sandals and traveled on foot. Servants usually performed this service. Jesus used this custom to teach us a lesson in humility. We should consider it a privilege to serve our brethren in even the most humble affairs of life. Romans 12:10

Manna for younger children, with image
This is designed for children under 10yr old makes it more practical and easy to understand at their level