Erethizō means to provoke or stir up — it can be used positively (stirring up to good works) or negatively (provoking to anger). It appears twice in the New Testament: Colossians 3:21 warns fathers not to erethizō their children (provoke/embitter them), and Hebrews 10:24 exhorts believers to consider how to stir up one another to love and good works (eis paroxysmon agapēs). The closely related paroxynō is used for sharper provocation (1 Cor 13:5 — love is not provoked; Acts 17:16 — Paul's spirit provoked by idols).
The two uses of erethizō define the two possible directions of stirring — toward life or toward bitterness. Colossians 3:21 identifies a specific failure point for fathers: harsh provocation that crushes a child's spirit. Hebrews 10:24 calls the whole community to intentional, positive stirring — considering (katanoeō, deliberate attention) how to provoke each other upward toward love and good deeds. Christian community is not passive coexistence; it is mutual provocation toward Christlikeness. The Greek word for this positive provocation, paroxysmos, gives us the English word 'paroxysm' — an intense outburst, here redirected toward love.