Synopsis of the Books of the Bible, by John Nelson Darby, [1857-62], at sacred-texts.com
The following commentary covers Chapters 19 through 23.
But having thus terminated the course of grace, the scene changes entirely. They do not keep the feast on the mountain, whither God, as He had promised, had led them-had "brought them, bearing them, as on eagles' wings, to himself." He proposes a condition to them: If they obeyed His voice, they should be His people. The people-instead of knowing themselves, and saying, "We dare not, though bound to obey, place ourselves under such a condition, and risk our blessing, yea, make sure of losing it"-undertake to do all that the Lord had spoken. The blessing now took the form of dependence, like Adam's, on the faithfulness of man as well as of God. Still farther was it from being, as ours, based on a fulfilled and accomplished redemption; it was not even based on an unconditional promise, as in the case of Abraham [See Note #1]. The people, however, are not permitted to approach God, who hid Himself in the darkness. In fact they undertook obedience far from God, in a state in which they could not approach Him in that majesty to which obedience was due. Nevertheless God gave all possible solemnity to the communication of His law, and sees it good that the people should fear before Him; but what can fear do towards giving power at a distance from Him? The feeling may, perhaps, be proper; but it is not proper to undertake to obey in such a state. Terror, and the condition of obedience when the people are far from God-such is the character of the law, a rule sent out to man, taken in its largest character, when man cannot approach God, but a barrier is set up, and the question of righteousness as the way of life raised and claimed from man when man is a sinner.
Moses, when God had spoken to the people, and the people dared no more to hearken, drew near to the thick darkness, and received the instructions of God for the people-moral and general instructions-relating to their possession of the land, in case they should enter upon it according to the covenant of the law. Two things are pointed out as to worship-the work of man, and his order, in which his nakedness will certainly be made manifest; and they are equally and together prohibited by God.
We have (as we may observe by the way) a beautiful type (chap. 21) of the devotedness of Christ to the church and to His Father, and His love to us. Having served already faithfully His full service as man, during His lifetime, He would remain a servant even in death for the sake of the Father, the church, and His people. He made Himself a servant for ever. (Compare John 13 for the present time, and Luke 12 even for glory).
Note #1
It is important for us to see that our standing before God does not rest on promise, but on accomplished redemption. All that concerned that and the basis of our assurance of faith is accomplished promise. Glory is in hope.