The answer is: Feet, hands and head

John 13:9 - Spiritually, Peter wanted to be completely cleansed.

In the intriguing moment captured in John 13, Peter's bold request to have Jesus wash not just his feet, but also his hands and head, reflects a deeper spiritual yearning. It’s some serious interpretation material! Feet were seen as the most lowly part of the body, and by insisting on a full cleanse, Peter's enthusiasm also showcases his understanding of the deeper human desire for connection and purity in spirit.

Interestingly, this moment can spark a dialog about humility. Jesus, by washing the disciples' feet, upended traditional societal norms. It wasn't common for a master to perform such menial labor – but He did so to show that true leadership comes from servitude. This has led to discussions and methods of service throughout ages, specifically the practice of foot washing in various Christian and even secular communities as a reminder of servitude.

Also worthy of trivia treasure is the fact that the act of bathing or washing in biblical times frequently had cultural implications. Not washing, particularly in the New Testament narrative, pointed to being unprepared or unworthy. Peter's insistence shows his passion, but there is also a universal call to invite full acceptance and holiness in one's life.

The dialogue prompts one to reflect: How often do we, like Peter, yearn to be wholly cherished and cleansed, seeking redemption beyond mere visible acts? The echoes of such spiritual cleansing resonate throughout many teachings and allow individuals to connect deeper with their authentic selves and principles.