Partiality
Partiality — favoring one person over another on grounds outside the matter at hand — surfaces in scripture both as a domestic wound and as a charge laid on those who govern others. The umbrella collects two angles: the explicit prohibition placed on a church overseer, and the household scene in which a father's preferential love sets brothers against a brother.
Forbidden Among Brethren
Paul's charge to Timothy puts partiality under the heaviest possible witness. The apostle binds the young overseer to a triple oath — God, Christ Jesus, and the elect angels — before specifying the conduct: "I charge [you] in the sight of God, and Christ Jesus, and the elect angels, that you observe these things without prejudice, doing nothing by partiality" (1 Timothy 5:21). The two prohibitions stand together. To act without prejudice is to come to a matter without a verdict already formed; to do nothing by partiality is to refuse to let preference decide the matter once it is in hand. The context (Paul has just been speaking of how to handle accusations against elders and the public correction of those who sin) frames partiality as a failure of office, not merely of feeling.
Effect on Other Children
The household at Hebron shows what partiality does to those on the receiving end of the slighted side. Jacob's preferential love for Joseph is registered not in the father's words but in the brothers' eyes: "And his brothers saw that their father loved him more than all his brothers; and they hated him, and could not speak peacefully to him" (Genesis 37:4). The favoritism is visible — they "saw" it — and the response is total: hatred and the loss of peaceable speech. Partiality from above produces enmity below; the brothers cannot even greet Joseph in the ordinary way. The narrative does not rebuke Jacob in this verse, but the consequence is laid bare: a household pulled out of peace because one son is loved more than all the rest.