John Calvin on Exodus 18:23

23. If thou shalt do this thing. What immediately follows, “and God command thee so,” may be taken in connection with the beginning of the verse, as if, in self-correction, Jethro made the limitation, that he did not wish his counsel to be obeyed, unless God should approve of it. Others extend it more widely, that if Moses followed God’s commands in all things, this moderation of his duties would be useful. However you take it, Jethro declares that he would have nothing conceded to him, which should derogate from God’s supreme authority; but that there was nothing to prevent Moses from following, as he had done, God as his leader, and still adopting the proposed plan. Yet he signifies that this was to be but temporary, when he adds, that the people should go in peace or prosperously into the land of Canaan. Jethro, then, had no wish to establish a law for posterity; but points out a remedy for present inconveniences, and a provisional arrangement, There is an obscurity here in the Latin, which I have not been able to remove. The words are, “atque (ut vulgo loquitur) modum promissionis ostendit.” The common language to which C. alludes may probably be that of the ancient grammarians. The Fr. is “par maniere de provision, (comme on dit.)” until the people should obtain a peaceful resting-place.