To touch another with the feet is considered an act of misdemeanor. Why is this so?

From “In Indian Culture, Why Do We…” by Swamini Vimalananda Radhika Krishnakumar.
Copyright: Central Chinmaya Mission Trust, Chinmaya Mission UK, www.chinmayauk.org

Man is regarded as the most beautiful, living breathing temple of the Lord! Therefore touching another with the feet is akin to disrespecting the divinity within him or her. This calls for an immediate apology, which is offered with reverence and humility.