Deuteronomy 31:20

Deuteronomy 31:20, in plain English

Once God brings them into the promised land and they prosper, they'll turn to other gods, reject Him, and break the covenant—exactly the cycle God already warned about.

Why it's here

Here's the tragic irony: prosperity becomes the danger. In the wilderness, Israel depended on God for every meal, every drink of water. But in the land flowing with milk and honey, they'll think they have what they need without God. Success can make you forget the One who made success possible. That's the warning.

Who's speaking

The Lord is speaking to Moses.

Where it sits in the story

This prophecy echoes throughout Israel's history. Solomon becomes wealthy and turns to foreign gods. Later kings see prosperity and think they don't need God's law anymore. The cycle continues until exile forces them back to dependence on God. Even today, it's one of the most human struggles: staying faithful when things are going well.

The scholarly reading

YHWH elaborates on Israel's predictable trajectory: prosperity will seduce them into forgetfulness; satiated and secure, they will abandon YHWH for idolatrous alternatives, thereby breaking the covenant.

Language and setting

The sequence 'eat their fill and prosper...turn to other gods...reject Me and break My covenant' describes what scholars call the 'prosperity problem'—material blessing paradoxically threatens spiritual fidelity. The Hebrew 'eat their fill' (וְאָכַל וְשָׂבַע, v'achal v'sava) employs the root שׂבע (sava', satisfied), suggesting surfeit as the condition of apostasy. This theological diagnosis appears repeatedly in biblical wisdom (Deuteronomy 6:10-12, 32:15, Hosea 13:6)—wealth breeds amnesia. The verb 'reject' (וְנָאַץ, v'na'atz) carries the sense of deliberate contempt, not mere negligence. This verse articulates what we might call 'covenantal psychology'—human beings are spiritually vulnerable precisely at moments of security. Calvin emphasized this passage in discussing how external circumstances test internal faith.

Voice

YHWH completing the prediction of Israel's future infidelity.

Significance

This final verse of the prophecy section completes YHWH's theodicy for Israel's coming judgment, establishing that apostasy flows not from divine foreordination but from the human heart's tendency toward idolatry when material pressures ease.

18And on that day I will surely hide My face because of all the evil they have done by turning to other gods.

19Now therefore, write down for yourselves this song and teach it to the Israelites; have them recite it, so that it may be a witness for Me against them.

20When I have brought them into the land that I swore to give their fathers, a land flowing with milk and honey, they will eat their fill and prosper. Then they will turn to other gods and worship them, and they will reject Me and break My covenant.

21And when many troubles and afflictions have come upon them, this song will testify against them, because it will not be forgotten from the lips of their descendants. For I know their inclination, even before I bring them into the land that I swore to give them.”

22So that very day Moses wrote down this song and taught it to the Israelites.

Read all of Deuteronomy 31 — Moses commissions Joshua and writes the law in a book. He knows they'll rebel — and writes a song to remind them why.