"Upon a ten-stringed instrument and upon the psaltery" (Ps. 92:8). All testimonies reliable to Israel are (celebrated) with ten (males). The harp upon which David played had ten strings. The testimony for the dead is through ten (males). The testimony for the (public) benediction of (God's) Name is through ten (males). The testimony of the covenant of circumcision is through ten (males). The testimony for Chalizah is through ten (males), as it is said, "And he took ten men of the elders of the city" (Ruth 4:2).