Genesis 23:17

Abraham insisted on paying in full so the ground would be his beyond dispute, bought in public before witnesses on the strength of what God had said about the land. Before Ephron offered anything, Abraham had already asked for the cave "for full price" (Genesis 23:9). The Hebrew is bekhesef male, literally in full silver, from male (H4392), full. Four hundred shekels is about four and a half kilograms of silver, a sum the whole gate could watch go onto the scales.

God is telling Abram to take possession of the land by faith, and to treat it as already his before he holds any deed. "Get up and walk around the land, through its length and breadth, for I will give it to you" (Genesis 13:17). The verb is halak (H1980) in a form that means to walk to and fro, to range across. In the ancient world walking a territory was a legal act; you took possession of ground by treading its length and breadth in the sight of witnesses. God tells Abram to enact ownership of erets (H776), land, that he holds no deed to and will not hold one to in his lifetime. The only plot Abram ever legally owns is the cave where he later buries Sarah (Genesis 23). Yet he is told to walk the whole of it as already his, because the word of the God who gives is a firmer title than any deed. Abram walks the promise before he sees it fulfilled.