Did the Edomites refuse supplies to Israel when they passed through their land, or did they furnish them? This apparent discrepancy revolves around two scriptures provided below:

Numbers 20:19-20: "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. And he said, Thou shalt not go through. And Edom came out against him with much people, and with a strong hand" (KJV).

Deuteronomy 2:28-29: "You will sell me food for money so that I may eat, and give me water for money so that I may drink, only let me pass through on foot, just as the sons of Esau who live in Seir and the Moabites who live in Ar did for me, until I cross over the Jordan into the land which the Lord our God is giving to us" (KJV).

The scripture in Numbers deals with the incident as Israel passed through Edom. The scripture in Deuteronomy deals with the incident after the fact. This (Deuteronomy 2:28-29) is when Israel was trying to pass through the land of Sihon, king of Heshbon. So, there appears to be a contradiction.

According to Haley's book listed below, the Edomites (sons of Esau) initially refused to allow Israel safe passage and provisions but later changed their minds once they realized they could economically benefit.

Further support for this idea is found in Deuteronomy 23:3-4. Here, we read the Lord is upset with the Ammonites and Moabites for not coming out to meet the Israelites with bread and water when they were making their way out of Egypt. This sounds very similar to the above incident with the Edomites.

But now notice again in Deuteronomy 2:28-29 where it says the Edomites (sons of Esau) and the Moabites did sell the provisions for money. This further supports the idea that after first denying the Israelites, both the Moabites and Edomites saw a way to be compensated economically.

Another possible answer to this alleged discrepancy is found in Deuteronomy 2:3-6: "Ye have compassed this mountain long enough: turn you northward. And command thou the people, saying, Ye are to pass through the coast of your brethren the children of Esau, which dwell in Seir; and they shall be afraid of you: take ye good heed unto yourselves therefore: Meddle not with them; for I will not give you of their land, no, not so much as a foot breadth; because I have given mount Seir unto Esau for a possession. Ye shall buy meat of them for money, that ye may eat; and ye shall also buy water of them for money, that ye may drink" (KJV).

Here, it looks like after seeing the Israelites and their numbers, the Edomites had second thoughts about trying to engage with the Israelites. They may have sold them the food and water after realizing the Israelites were just passing through. Why waste their men on fighting the Israelites, who appeared to be a formidable foe?

A bit more detail on this idea is provided in the Keil and Delitzsch commentary: On the western side of their mountains the Edomites had refused permission to the Israelites to pass through their land (Num. 20:18ff.), as the mountains of Seir terminate towards the Ghor (the Arabah) in steep and lofty precipices, and there are only two or three narrow wadys which intersect them from west to east; and of these the Wady Ghuweir is the only one which is practicable for an army, and even this could be held so securely by a moderate army, that no enemy could force its way into the heart of the country (see Leake in Burckhardt, pp. 21, 22; and Robinson, ii. p. 583). It was different on the eastern side, where the mountains slope off into a wide extent of tableland, which is only slightly elevated above the desert of Arabia. Here, on the weaker side of their frontier, the Edomites lost the heart to make any attack upon the Israelites, who would now have been able to requite their hostilities (Keil and Delitzsch Commentary on the Old Testament, 1.747).

Let's take a look at how this text is rendered in the NASB Version:

"You will sell me food for money so that I may eat, and give me water for money so that I may drink, only let me pass through on foot, just as the sons of Esau who live in Seir and the Moabites who live in Ar did for me until I cross over the Jordan into the land which the Lord our God is giving to us" (Deuteronomy 2:28-29 NASB).

Here, we have a record of Moses saying that the Edomites and the Moabites sold him and the Israelites food, not necessarily that they (Edom) let him pass through their land. In fact, Judges 11:14-18 makes it clear that the Israelites didn't even pass through the land of Edom or Moab.

So, how did the Israelites manage to purchase resources from the Edomite and Moabite people without ever entering their countries? Well, the "sons of Esau who live in Seir" (v. 29) lived on the border of Edom and allowed the Israelites to purchase food and water and, in a sense, "pass through," although Israel remained on the border of Edom. This was also the case regarding the interaction between Israel and the Moabites, seeing as Ar lies on the eastern border of Moab.

Thus, we see that the text found in Deuteronomy 2:26-29 is in harmony with the narrative found in Numbers 20:18-21. When Israel was prohibited from entering Edom, the text states they "turned away from him" (Numbers 20:21). But after time elapsed and some significant events took place, Israel set out again, but to go around Edom this time (Numbers 21:4). This was when the "Edomites in Seir" (Deuteronomy 2:29) sold the Israelites food and water on the border of Edom. Although the Edomites refused Israel passage through the midst of their land, the implication is that Edom did allow Israel to purchase food.

Deuteronomy 2:4 is also important to consider. Isn't the Lord expressly stating that the Israelites would pass through the land of Edom? A closer look at the text reveals that there is no discrepancy:

"…and command the people saying, 'You will pass through the territory of your brothers the sons of Esau who live in Seir; and they will be afraid of you so be careful'" (Deuteronomy 2:4 NASB).

The key is found in looking at the Hebrew. The phrase rendered "pass through" is the Hebrew word abar, which can also be used of "passing by." In Genesis 18:3, Abraham begged the three men not "to pass by" him but to stop and refresh themselves (Vine's, pp. 172-173).

Also, the word gebul, rendered "territory" in this text (Deuteronomy 2:4), literally means "border" (Strong's, Hebrew 1366). In the KJV, the word gebul is translated as "coast."

Sources: "How is Deut. 2:29 reconciled with Num. 20:18-21?" Biblical Hermeneutics, https://hermeneutics.stackexchange.com/questions/4212/how-is-deut-229-reconciled-with-num-2018-21

Alleged Discrepancies of the Bible, by John W. Haley, (Grand Rapids: Baker Book House), p. 335.

Keil & Delitzsch Commentary on the Old Testament, Volume 1, (Peabody: Hendrickson Publishers, Inc.), 2001.