The answer is: Take off his sandals

Josh 5:15

In the intriguing narrative of Joshua, when the captain of the Lord's host appears to him, it's not just about military might but about humility and reverence. The command to take off his sandals was reminiscent of Moses’ encounter with God at the burning bush (Exodus 3:5). In both instances, the act of removing shoes symbolizes entering into a sacred space, a moment where the earthly and divine meet.

This poignant command illustrates the idea of holiness, especially in how one interacts with God. The ground is marked as holy not just because of the divine presence, but it suggests a setting apart - a reminder for Joshua, and for us, of the need for reverential approach when we engage with the divine. Shoes, often dirtied by daily activities, carry the metaphorical weight of our worldly burdens. By removing them, Joshua symbolically sheds those worldly worries and stands before the divine, fully present.

Interestingly, the Jordan River—which they were about to cross—is also symbolic of transition and transformation. In the grand scheme of the Israelites’ journey, invoking simple acts like taking off sandals speaks volumes about the profound encounters we have in life.

Moreover, the captain's visitation reveals a theme prevalent throughout Scripture: It's about hearing and heeding the divine voice guiding humankind moments of significant change. It prompts each of us to ponder what strips away our spiritual heaviness as we tread along our journey.