What does it mean to ‘stand the stones’?

It's best explained in the story of Jacob:

In Genesis chapters 28 & 31, Jacob stands stones on two different occasions to mark life changing events. When he dreams of the ladder to heaven, he awakens in the morning, proclaiming “The LORD is in this place and I was not aware of it!” He stands the stone he had used as a pillow to mark that place forever as a place where he met with God. A few chapters later, Jacob and his father-in-law, Laban, make a covenant with one another to not harm each other or their families any further. They heap stones in a pile and Laban declares “let this pile be a witness to the covenant between us.” Seeking reconciliation is a constant theme in Jacob’s life, and he marks those sacred moments by standing stones so that he will remember.

Let us honor the moments of reconciliation, experienced in worship or community, as Jacob did,
by remembering, by standing the stones.