Sâthar (סָתַר, Strong's #5641), “to conceal, hide, shelter.” This verb and various derivatives are found in modern Hebrew as well as in biblical Hebrew. Sâthar occurs approximately 80 times in the Old Testament. The word is found for the first time in Gen. 4:14 as Cain discovers that because of his sin, he will be “hidden” from the presence of God, which implies a separation.
In the so-called Mizpah Benediction (which is really a warning), sâthar again has the sense of “separation”: “The Lord watch between me and thee, when we are absent one from another” (Gen. 31:49). To “hide oneself” is to take refuge: “Doth not David hide himself with us …?” (1 Sam. 23:19). Similarly, to “hide” someone is to “shelter” him from his enemy: “… The Lord hid them” (Jer. 36:26).
To pray, “Hide thy face from my sins” (Ps. 51:9), is to ask God to ignore them. But when the prophet says, “And I will wait upon the Lord, that hideth his face from the house of Jacob …” (Isa. 8:17), he means that God’s favor has been withdrawn. Similarly, Judah’s sins have “hidden” God’s face from her (Isa. 59:2).