Leviticus 19:15
13 You must not oppress your neighbor or commit robbery against your neighbor. You must not withhold the wages of the hired laborer overnight until morning. 14 You must not curse a deaf person or put a stumbling block in front of a blind person. You must fear your God; I am the Lord. 15 “‘You must not deal unjustly in judgment: You must neither show partiality to the poor nor honor the rich. You must judge your fellow citizen fairly. 16 You must not go about as a slanderer among your people. You must not stand idly by when your neighbor’s life is at stake. I am the Lord. 17 You must not hate your brother in your heart. You must surely reprove your fellow citizen so that you do not incur sin on account of him.
Psalm 82:2
1 A psalm of Asaph. God stands in the assembly of El; in the midst of the gods he renders judgment. 2 He says, “How long will you make unjust legal decisions and show favoritism to the wicked? (Selah) 3 Defend the cause of the poor and the fatherless. Vindicate the oppressed and suffering. 4 Rescue the poor and needy. Deliver them from the power of the wicked. 5 They neither know nor understand. They stumble around in the dark, while all the foundations of the earth crumble.
Notes and References
"... “How long?” is an expression found in some laments (see Psalm 90:13). Here, however, the question has the character of a charge against the gods (compare Psalm 94:3–5; Exodus 10:7; 1 Samuel 1:14; Jeremiah 4:14, 21; Psalm 74:10; Proverbs 1:22). Verse 2 is literally “You lift up the faces of the wicked,” i.e., you show respect, favor, and partiality. Verse 3, the word refers to the “weak / lowly / helpless” people (compare e.g., Leviticus 19:15; Judges 6:15; Job 31:16; Psalm 113:7; Isaiah 10:2; Jeremiah 5:4) ..."
Tate, Marvin E. Word Biblical Commentary: Psalms 51-100 (p. 586) Word Books, 2000