The answer is: Blue

Exo 28:31 - the middle garment, beneath the ephod and above the coat, made from one piece of fabric and similar in design to the robe Christ was wearing at the crucifixon (John 19:23)

In the rich tapestry of biblical symbolism, the color blue often represents the divine or heavenly, linking the earthly to the sacred. In Exodus 28:31, the priest’s robe was indeed blue, signifying both nobility and a life set apart for a sacred calling. Blue was a popular color in ancient garments because it stood out against the landscape and caught the eye, embodying the idea of being "above" mundane existence.

Now, isn't it fascinating to think about the connection between the priest's robe and important figures in the Bible? The shades of blue in Wooed royal garments even suggest a link to heaven itself, reminiscent of the sky reflecting God’s majesty—and this idea weaves through numerous biblical accounts.

When witnessing the crucifixion, it’s noteworthy that the soldiers cast lots for the seamless garment of Jesus, which mirrors the design of the priestly robe. This isn’t merely coincidence; it reinforces the idea of Christ as a high priest, bridging the human and the divine.

Serving as a priest meant conducting rituals, teaching others, and maintaining the spiritual lifeblood of the community. Both the robes and coats were signifiers of their roles, crafted to communicate not just formality but purpose. In this way, the color blue is a compelling reminder of a connection to spiritual leadership, intriguing narratives, and ultimate sacrifice in the grand story of faith.