No Ammonite or Moabite or any of their descendants may enter the assembly of the LORD, not even in the tenth generation. For they did not come to meet you with bread and water on your way when you came out of Egypt, and they hired Balaam son of Beor from Pethor in Aram Naharaim to pronounce a curse on you. — Deuteronomy 23:3–4

The Torah portion for this week is Ki Teitzei, which means “when you go out,” from Deuteronomy 21:10–25:19, and the Haftorah is from Isaiah 54:1–10.

I was deeply moved by a recent news story about a mother named Kellie Haddock who went on a mission to locate and thank the medical staff who had saved her son’s life 10 years earlier. On that fateful day, Kellie, her three-week-old infant Eli, and her husband AJ were in a car accident that immediately killed AJ and severely injured the others. The prognosis for the infant didn’t leave much hope, but the determined team of medical staff didn’t give up.

Ten years later, Eli Haddock is alive and well, and his mother wanted to thank the people who made it possible. Armed with a camera crew, she did. Visibly touched to the core, one nurse’s eyes filled with tears as she explained, “I’ve never been thanked before.”

Such is the power of saying, “Thank you.”

In this week’s Torah portion, we read the commandment that the Israelite women were forbidden to marry men from the nations of Ammon and Moab, “For they did not come to meet you with bread and water on your way when you came out of Egypt . . .”

In Numbers 21, the Israelites had requested permission to walk through the lands of Ammon and Moab, saying, “Let us pass through your country. We will not turn aside into any field or vineyard, or drink water from any well. We will travel along the King’s Highway until we have passed through your territory” (Numbers 21:22). However, not only did these nations not allow the children of Israel to pass through, they also waged war on them. It seems odd then that God wrote off these nations because they didn’t bring the Israelites food and water. Certainly what they did do was far worse!

By emphasizing the failure of Ammon and Moab to show hospitality to the Israelites, Scripture is teaching us a lesson in the importance of gratitude. Remember, Ammon and Moab were the descendants of Lot. Lot’s life was saved twice by his uncle Abraham. Here, Abraham’s descendants were passing by their land, and they failed to express gratitude for Abraham’s role in their survival.

Gratitude is the greatest guard against animosity. If the people of Ammon and Moab would have had a grateful spirit, there wouldn’t have been a war (which they ended up losing). Their lack of gratitude led to worse behavior, and ultimately their downfall.

Similarly, we need to cultivate a spirit of gratitude in our own lives in order to maintain peaceful and meaningful relationships. When we focus on the good that others have done for us, we are far less likely to fall into an altercation with them and far more likely to enjoy the people in our lives.