1 Peter 2:19–20 addresses the specific situation of enduring unjust treatment: "For this is thankworthy, if a man for conscience toward God endure grief, suffering wrongfully. For what glory is it, if, when ye be buffeted for your faults, ye shall take it patiently? but if, when ye do well, and suffer for it, ye take it patiently, this is acceptable with God." Peter distinguishes between suffering for your own fault and suffering while doing right. The second is described as acceptable — the Greek charis, literally grace — before God. The unjust treatment of someone doing good work is specifically within God's sight and approbation.
Psalm 82:3–4 contains God's explicit instruction about justice for the oppressed: "Defend the poor and fatherless: do justice to the afflicted and needy. Deliver the poor and needy: rid them out of the hand of the wicked." This is not a general call to be nice. The Hebrew shaphat — 'defend' — is the legal word for judicial advocacy. God takes sides in cases of unjust treatment. He is not a neutral observer.
Commentary is from a charismatic Protestant perspective, drawing on KJV text and public-domain sources including Spurgeon, Andrew Murray, and Matthew Henry.