The stones were for the names of the sons of Israel, twelve, corresponding to the number of ¹  their names. Each name corresponding to one of the twelve tribes was like the engravings of a seal.

and Moses wrote down all the words of the Lord. Early in the morning he built ¹  an altar at the foot ²  of the mountain and arranged ³  twelve standing stones ⁴  – according to the twelve tribes of Israel.