Kabbalah do Samuela I 15:29

(Note that it) is written "upon his thigh" and not 'upon his thighs'. This is the fourth grade, (i.e. Netzach) from where no prophecies were issued until Samuel arrived. About it, it is written: "And also the Eternal One (Heb. Netzach) of Yisrael" (I Samuel 15:29). (Netzach) which had been weak ever since Jacob the patriarch was endangered by the minister of Esau, was thus firmly reestablished.

“And give ear to His commandments,” refers to Netzach, for one should not insert this sign into a heathen woman, nor be false with it to Netzach. For it is written: “And also the Eternal One (lit. ‘Netzach’) of Yisrael will not lie” (I Shmuel 15:29). And he who observes this, THE HOLY COVENANT, fulfills His commandments, as is written: “For you shall worship no other El” (Shemot 34:14).