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)

The robe worn by the priest in the book of Exodus, often noted for its striking blue hue, wasn’t just a fashion statement. In ancient times, color spoke volumes—they weren't simply shades but imbued with meaning and symbolism. Blue, for instance, often represented purity and heavenliness. This connection adds depth to the Hebrews' religious experience, weaving the heavenly elements into their earthly rituals.

The mention of the priestly robe connects intriguingly with the imagery found in the New Testament. When John recounts the crucifixion of Christ, the soldiers cast lots for Jesus' seamless robe (John 19:23). Here’s where it gets fascinating: the seamless robe also serves as a metaphor for unity and the wholeness of Christ's divine authority—a beautiful echo of the meticulous craftsmanship expected of priestly garments.

Moreover, here's a fun tidbit for you! The notion of blue as heavenly invites comparisons to the ancient practice of using dye made from the murex snail, which was quite expensive and precious. This refined blue dye was indeed a symbol of wealth as well as religious significance back then. So, as we ponder on that blue robe, we delve into traditions that stretch through time—offering a glimpse of how belonging to a community of faith was visually represented through clothing. It's compelling to think that a simple color choice plays a chipper role in our understanding of biblical teachings and captures a timeless narrative that weaves from Exodus to the New Testament.