Numbers 20:19

And the children of Israel said unto him, We will go by the high way: and if I and my cattle drink of thy water, then I will pay for it: I will only, without doing any thing else, go through on my feet.

Cross-reference

Deuteronomy 2:6 commands Israel to buy food and water from Edom, which matches the offer to pay for water made here in Numbers 20:19.

Deuteronomy 2:28 uses nearly identical wording—offering payment for food and water and requesting passage—now directed to Sihon instead of Edom.