Om is the bow, the Self is the arrow, and Brahman is called its target. It is to be pierced by one who is undistracted; then one becomes one with it, like the arrow.
प्रणवो धनुः शरो ह्यात्मा ब्रह्म तल्लक्ष्यमुच्यते । अप्रमत्तेन वेद्धव्यं शरवत्तन्मयो भवेत् ॥ ४॥