The Moab nation was started with an incestuous encounter between Lot [Abraham’s nephew] and Lot’s firstborn daughter.

Gen 19:36  Thus both the daughters of Lot were with child by their father.

Gen 19:37  The firstborn bore a son and called his name Moab; he is the father of the Moabites to this day.

Moab forms part of the nation of modern-day Jordan.

The Moabites are one of the ten nations, which combine to destroy Israel.

Psa 83:4  They have said, “Come, and let us cut them off from being a nation, That the name of Israel may be remembered no more.”

Psa 83:5  For they have consulted together with one consent; They form a confederacy against You:

Psa 83:6  The tents of Edom and the Ishmaelites; Moab and the Hagrites;

Isaiah 15 gives an account of the eventual punishment of the Moabites.

Isa 15:1  The burden against Moab. Because in the night Ar of Moab is laid waste And destroyed, Because in the night Kir of Moab is laid waste And destroyed,

Isa 15:2  He has gone up to the temple and Dibon, To the high places to weep. Moab will wail over Nebo and over Medeba; On all their heads will be baldness, And every beard cut off.

Isa 15:3  In their streets they will clothe themselves with sackcloth; On the tops of their houses And in their streets Everyone will wail, weeping bitterly.

Isa 15:4  Heshbon and Elealeh will cry out, Their voice shall be heard as far as Jahaz; Therefore the armed soldiers of Moab will cry out; His life will be burdensome to him.

Isa 15:5  “My heart will cry out for Moab; His fugitives shall flee to Zoar, Like a three-year-old heifer. For by the Ascent of Luhith They will go up with weeping; For in the way of Horonaim They will raise up a cry of destruction,

Isa 15:6  For the waters of Nimrim will be desolate, For the green grass has withered away; The grass fails, there is nothing green.

Isa 15:7  Therefore the abundance they have gained, And what they have laid up, They will carry away to the Brook of the Willows.

Isa 15:8  For the cry has gone all around the borders of Moab, Its wailing to Eglaim And its wailing to Beer Elim.

Isa 15:9  For the waters of Dimon will be full of blood; Because I will bring more upon Dimon, Lions upon him who escapes from Moab, And on the remnant of the land.”

Moab will become as Sodom.

Zep 2:8  “I have heard the reproach of Moab, And the insults of the people of Ammon, With which they have reproached My people, And made arrogant threats against their borders.

Zep 2:9  Therefore, as I live,” Says the LORD of hosts, the God of Israel, “Surely Moab shall be like Sodom, And the people of Ammon like Gomorrah— Overrun with weeds and saltpits, And a perpetual desolation. The residue of My people shall plunder them, And the remnant of My people shall possess them.”

Zep 2:10  This they shall have for their pride, Because they have reproached and made arrogant threats Against the people of the LORD of hosts.

Moabites are not completely destroyed, but they are left a small small nation after their punishment.

Isa 16:13  This is the word which the LORD has spoken concerning Moab since that time.

Isa 16:14  But now the LORD has spoken, saying, “Within three years, as the years of a hired man, the glory of Moab will be despised with all that great multitude, and the remnant will be very small and feeble.”

Jer 48:47  “Yet I will bring back the captives of Moab In the latter days,” says the LORD. Thus far is the judgment of Moab.

That is their punishment for helping to bring down God’s chosen nation: Israel.