Holy Zohar text. Daily Zohar -143.

Tikkun #13

King David’s harp had 5 strings for to connect to the 10 Sefirot, Keter, Chokmah, Binah, Zeir Anpin (6 Sefirot) and Malchut. It is implied in the Song of Ascend (Psalms 121:1) with 5 times YHVH.

With the 5 string harp King David made 10 types of songs to climb the spiritual levels. Every song is also in one of the aspects of the YHVH name.