The Lord God of gods - The original words are exceedingly emphatic, and cannot be easily translated. אל אלהים יהוה El Elohim Yehovah, are the three principal names by which the supreme God was known among the Hebrews, and may be thus translated, the strong God, Elohim, Jehovah, which is nearly the version of Luther, der starcte Gott der Herr, "The strong God the Lord." And the Reubenites, by using these in their very solemn appeal, expressed at once their strong unshaken faith in the God of Israel; and by this they fully showed the deputation from the ten tribes, that their religious creed had not been changed; and, in the succeeding part of their defense they show that their practice corresponded with their creed. The repetition of these solemn names by the Reubenites, etc., shows their deep concern for the honor of God, and their anxiety to wipe off the reproach which they consider cast on them by the supposition that they had been capable of defection from the pure worship of God, or of disaffection to their brethren.

Save us not this day - This was putting the affair to the most solemn issue; and nothing but the utmost consciousness of their own integrity could have induced them to make such an appeal, and call for such a decision. "Let God the Judge cause us to perish this day, if in principle or practice we have knowingly departed from him."

let the Lord

Genesis 9:4 But flesh with the life thereof, which is the blood thereof, shall you not eat.

Deuteronomy 18:19 And it shall come to pass, that whoever will not listen to my words which he shall speak in my name, I will require it of him.

1 Samuel 20:16 So Jonathan made a covenant with the house of David, saying, Let the LORD even require it at the hand of David's enemies.

2 Chronicles 24:22 Thus Joash the king remembered not the kindness which Jehoiada his father had done to him, but slew his son. And when he died, he said...

Psalm 10:13,14 Why does the wicked scorn God? he has said in his heart, You will not require it...

Ezekiel 3:18 When I say to the wicked, You shall surely die; and you give him not warning, nor speak to warn the wicked from his wicked way...

Ezekiel 33:6,8 But if the watchman see the sword come, and blow not the trumpet, and the people be not warned; if the sword come...

And thou, Bethlehem Ephratah, too little to be among the thousands of Judah
"And thou, Bethlehem Ephratah, too little to be among the thousands of Judah, out of thee shall come forth unto Me (one) [Pg 480] to be Ruler in Israel; and His goings forth are the times of old, the days of eternity." The close connection of this verse with what immediately precedes (Caspari is wrong in considering iv. 9-14 as an episode) is evident, not only from the [Hebrew: v] copulative, and from the analogy of the near relation of the announcement of salvation to the prophecy of disaster …
Ernst Wilhelm Hengstenberg—Christology of the Old Testament