Is in the Old Testament used as a designation of true piety (Prov. 1:7; Job 28:28; Ps. 19:9). It is a fear conjoined with love and hope, and is therefore not a slavish dread, but rather filial reverence. (Comp. Deut. 32:6; Hos. 11:1; Isa. 1:2; 63:16; 64:8.) God is called “the Fear of Isaac” (Gen. 31:42, 53), i.e., the God whom Isaac feared. A holy fear is enjoined also in the New Testament as a preventive of carelessness in religion, and as an incentive to penitence (Matt. 10:28; 2 Cor. 5:11; 7:1; Phil. 2:12; Eph. 5:21; Heb. 12:28, 29).
–Easton's Bible Dictionary