One of the traits of God is that of His immutability. He is stable — unchanging in His nature (Malachi 3:6; Hebrews 13:8). In illustrating this quality of the Creator, James writes: “. . . with whom [God] can be no variation, neither shadow that is cast by turning” (1:17). Nature changes, but Jehovah does not.
Of special interest here, though, is the expression “shadow that is cast by turning.” The word “turning” is from the Greek trope, which W.E. Vine says is “especially used of the revolution of the heavenly orbs” (Expository Dictionary of New Testament Words, IV, p. 163).
In the Greek version of the Old Testament, the term is used of the “changes” that take place in the heavens (Job 38:33). It is entirely possible that James is suggesting that whereas shadows are altered by the “turning” of the earth upon its axis (thus changing its relationship to the sun), by way of contrast God does not so change.
If this is the case, we have here a remarkable statement, wonderfully accurate from a scientific viewpoint, that appears to be considerably ahead of its time. This may be an example of inspired scientific foreknowledge.
Some (e.g., Lenski) object to this approach, suggesting that James’ language must involve something his readers would understand. Well, they could understand the movement of a shadow without understanding the technicalities that would produce such an effect. Second, if biblical writers always conformed their messages to the level of antique comprehension, the sacred volume would be vastly different!
Thus, underline “turning,” and note: Possible allusion to the earth’s rotation. We are not attempting to be dogmatic with this suggestion, but it certainly should not be dismissed.