The Hebrew verb yanah means to oppress, to mistreat, or to do wrong to someone — particularly the vulnerable. It describes the abuse of power against those who cannot defend themselves, and is consistently condemned in the Torah and Prophets.
The Law of Moses specifically forbids yanah against foreigners (Exodus 22:21), reminding Israel that they were once strangers in Egypt. The prophets use the word to indict Israel's social injustice — the strong wronging the weak. Its use creates a moral framework that connects personal ethics to covenant faithfulness.
Theologically, yanah reflects God's deep concern for justice and His identification with the vulnerable. Oppression of the powerless is not a minor social issue but a covenant violation that provokes divine judgment.