Zeroa is the word for arm or shoulder, frequently used as a powerful metaphor for strength, might, and power. Just as the arm is the instrument of action and force, zeroa came to symbolize the powerful action of God in history. In Deuteronomy and the Psalms, God's 'outstretched arm' (zeroa netuyah) became a standard phrase describing the Exodus deliverance.
The 'arm of the Lord' is one of the most potent theological images in Scripture. Isaiah 53:1 asks 'to whom has the arm of the LORD been revealed?' — then answers that the Servant Himself is the arm of the Lord made flesh. The New Testament echoes this: Christ is the power of God (1 Cor 1:24). To trust God's arm is to trust His ability to act decisively in history. The church is called to lean not on human strength but on the outstretched arm of God.