1:4

let endurance complete its work: When under trial, Christians might wish that the hardships they face would end quickly. They might even be tempted to violate Jehovah’s principles in order to avoid a trial. James reminds Christians that undergoing such trials can help to build qualities that are precious to God, especially endurance. (See study note on Ro 5:3.) Speaking about “endurance” as used in the Scriptures, one reference work describes it as “the spirit which can bear things, not simply with resignation, but with blazing hope.” The same work adds: “It is the quality which keeps a man on his feet with his face to the wind. It is the virtue which can transmute the hardest trial into glory because beyond the pain it sees the goal.”

let . . . complete its work, so that you may be complete: The Greek word rendered “complete” is used twice in this verse and can convey a broad range of meanings. In the first occurrence, it conveys the idea “let endurance finish its work.” In the second occurrence, it could be translated “so that you may be full-grown [mature; perfect].” (Compare Mt 5:48 and study note; Eph 4:13; Php 3:15.) In the Septuagint, the same word is used to convey the meaning of “faultless” (Ge 6:9) or “blameless” (2Sa 22:26). It can also describe a heart that is “complete” in its devotion to Jehovah.​—1Ki 8:61 and ftn.

sound in all respects: The single Greek term rendered “sound in all respects” may also convey the meaning of “whole” or “blameless.” By combining the terms “complete and sound in all respects,” James expresses confidence that humans​—despite being imperfect​—can meet a lofty standard of faithfulness. James conveys an idea similar to the concept of integrity mentioned in the Hebrew Scriptures, that is, whole, or complete, devotion to Jehovah. (Jos 24:14 and ftn.; Job 27:5; Ps 26:1; 101:2 and ftn.) James thus emphasizes that endurance can help make an imperfect human complete in the sense of remaining faithful to Jehovah and keeping integrity even under trial.​—See also Job 1:1, 8; 2:3.