Psalm 106 recounts the history of Israel's rebellion against God after the Exodus. Verse 35, "but mixed themselves with the nations, and learned their works," speaks to a key aspect of that rebellion: assimilation and idolatry.

Here's a breakdown of what the verse means:

"but mixed themselves with the nations": This refers to the Israelites choosing to live among and integrate with the surrounding Gentile nations rather than maintaining a distinct identity as God's chosen people. God had warned them against this, fearing their cultural practices and worship of other gods would lead them astray. This mixing involved intermarriage, social interaction, and adopting aspects of the surrounding cultures.

"and learned their works": This goes beyond mere co-existence. It means the Israelites actively adopted the practices, customs, and most significantly, the religious practices of the pagan nations. "Their works" encompasses their whole way of life, but particularly refers to:

Idolatry: Worshipping false gods and idols. This was a direct violation of God's commandments.
Immoral practices: Participating in the often corrupt and even depraved customs associated with pagan religions.
Unjust behavior: Adopting the unfair social and economic practices of the surrounding nations, rather than adhering to God's principles of justice and righteousness.

In essence, the verse highlights the Israelites' failure to remain faithful to their covenant with God. Instead of being a light to the nations and maintaining their distinct identity, they compromised their faith by embracing the ways of the world around them. This led to spiritual and moral decay, ultimately incurring God's judgment.

The verse serves as a cautionary tale about the dangers of assimilation and the importance of remaining true to one's faith, even when it is difficult or unpopular. The Israelites' experience demonstrates the temptation to conform to the surrounding culture and the potential consequences of abandoning God's principles.