Handbreadth
Handbreadth was a basic unit of linear measurement in the ancient world, defined as the width of four fingers held together across the palm of the hand—approximately three to four inches (7.5–10 cm) in modern equivalents. In tabernacle construction, a handbreadth described the width of the golden border around the table of showbread (Ex. 25:25; 37:12) and the thickness of the rim of the bronze sea in Solomon's temple (1 Kings 7:26; 2 Chr. 4:5).
The Psalmist uses the handbreadth figuratively to express the brevity of human life: thou hast made my days as a handbreadth; and mine age is as nothing before thee (Ps. 39:5)—contrasting the fleeting span of human existence with the eternal perspective of God. The handbreadth belonged to a system of body-based measurements common throughout the ancient Near East, including the cubit (elbow to fingertip), span (spread hand from thumb to little finger), and finger-width, all of which appear in the technical specifications of Israelite sacred architecture.