Jeremiah 34:18

And I will give the men that have transgressed my covenant, which have not performed the words of the covenant which they had made before me, when they cut the calf in twain, and passed between the parts thereof,

Passed between the parts thereof - the contracting parties in the "covenant" (not here the law in general, but their covenant made before God in His house to emancipate their slaves, Jeremiah 34:8) passed through the parts of the animal cut in two, implying that they prayed so to be cut in sunder (; Greek, cut him in two) if they should break the covenant (; ).