The answer is: Untie his sandals

Mark 1:7 - Which was work of servants and so he was showing great humility, saying he was not worthy to be a servant of the man who should come after him.

John the Baptist's declaration in Mark 1:7, where he says he is unworthy to untie Jesus’ sandals, is rich in meaning. To untie someone's sandals was indeed considered a task for the lowliest of servants. This emphasizes John's deep humility and recognition of his role as a forerunner to someone infinitely greater—Jesus, whom he saw as the Messiah.

Interestingly, this notion of being humble and self-aware echoes throughout the teachings of Jesus. For example, in Matthew 23:12, we find a similar theme: "For those who exalt themselves will be humbled, and those who humble themselves will be exalted." It creates a beautiful literary connection that speaks to a broader biblical principle: greatness is achieved through service and humility.

Moreover, sandals in that context function almost like a metaphor for our journeys. Untying and washing sandals could symbolize the purification and preparation needed for those embarking on a foundational path. It's a reminder of Jesus washing his disciples’ feet, fulfilling not just the role of a teacher but also that of a servant (John 13:1-17).

Did you know that ritual washing was also common in Jewish tradition? It indicates that John was not only making a statement about humility but also hinting at the coming purification that Jesus embodies in his mission. Thus, this tiny act of untying sandals becomes a profound moment of prophetic significance, encapsulating the humbling nature of true leadership and devotion.