The Hebrew verb atsar means to restrain, close, shut, or hold back. It is used of restraining rain (Deuteronomy 11:17), closing the womb (Genesis 16:2), restraining enemies, and of God's sovereign shutting and opening. It conveys the idea of divine control over natural and human powers.
God's sovereign power to open and close, restrain and release, runs throughout Scripture. He restrains rain as covenant discipline (Deuteronomy 11:17; 1 Kings 17:1) and opens it as blessing. He closes and opens wombs (Genesis 16:2; 20:18; 1 Samuel 1:5-6), demonstrating that life belongs to Him. Elijah's power to shut the heavens (1 Kings 17:1; James 5:17) and the two witnesses in Revelation 11:6 derive from this principle. The Servant's suffering includes atsar: "by oppression and judgment he was taken away" (Isaiah 53:8) — restrained, held back in death, yet released in resurrection.