Leaders Over Thousands

Rashi:"But you shall choose"
with the Divine Spirit that is upon you

"men of substance"
wealthy men, who do not have to flatter or show favoritism. 

"men of truth"
These are people who keep their promises, upon whose words one may rely, and thereby, their commands will be obeyed.

"who hate monetary gain"
Who hate [to have] their own property in litigation, like [the Talmudic adage] that we say: Any judge from whom money is exacted through litigation is not [fit to be] a judge. 

"leaders over thousands"
They were six hundred officers for six hundred thousand [men].

"leaders over hundreds"
They were six thousand. 

"leaders over fifties"
Twelve thousand

"leaders over tens"
Sixty thousand. [Rashi lists the number of each category of judges, which appears to be superfluous, because the Torah should start with the lowest denomination and ascend to the highest instead of starting with the highest and descending to the lowest. Rashi answers that it starts with the highest officers because they are the lowest number.]

There is no Baal HaTurim on this verse.

Targum Yonatan: When you are with the people who seek instruction from before the Lord, you should take their affair before G‑d, and give them counsel about the statutes and laws, make them understand the prayer they are to offer in the house of congregation, the manner of visiting the sick, of burying the dead, of being fruitful In doing good, and in the work and process of justice, and how to conduct themselves among the wicked. But you should elect from all the people men of ability who fear G‑d, upright men who hate to receive the money of dishonesty, and appoint them to be heads of thousands, of hundreds, of fifties, and of tens.

Ohr HaChayim: "Men of substance"
men who are capable of leading a great multitude of people. Every assembly and gathering is called "chayil" substance, and it does not apply only to soldiers going forth to war. "Hating unjust gain" means men who disdain their own money in a law suit." That is what Rashi said, but Ramban believes it means those who love the truth and hate oppression. When they see oppression and violence, they cannot tolerate them, their whole desire being only to "deliver the spoiled out of the land of the oppressor." (Jeremiah 21:12)

Ohr HaChayim: Moses should look for suitable candidates, and that as Moses would do the appointing, he could view himself as the judge seeing his appointees were his delegates.

"From amongst the people"
Moses might find candidates acceptable to him he should not appoint them until they also proved acceptable to all the people and the people asked for these men to be appointed as judges.

Yitro merited that the portion bear his name. While it is true that Yitro paid honor to Moses the servant of G‑d, G‑d repaid him by honoring him, but G‑d could have found other means to compensate Yitro for good deeds. Why did the Torah have to create an impression that if it had not been for Yitro a priest from Midian, Moses together with G‑d's chosen people would not have known how to administer Israel's affairs?
...there are great and intelligent men among the nations of the world.
G‑d wanted to show the Jewish people already at that time and for all future generations that there are great and intelligent men among the nations of the world. Yitro was an enlightened Gentile who demonstrated this point beyond question. It is to teach us that if G‑d chose the Jewish people to be His people, it is not because of the have superior intellectual capabilities. Rather it was a reward for the loyalty the Patriarchs had shown Him as an act of love towards this people. So even according to the opinion (Rashi, among others) that Yitro arrived in the desert after the Torah was given, the reason that the Torah reports his arrival before it reports the revelation shows that the Torah wishes us to learn the lesson that although there are more wise men among the Gentiles, that G‑d decided to focus his energy on us, thus giving us an additional duty as Jews, to praise G‑d for having chosen the Jews as an act of love.

Zohar Yitro 78:
He opened with the quote, "Moreover you shall provide out of all the people able men, such as fear G‑d, men of truth, hating unjust gain". But it is written: "you shall behold" instead of, 'you shall choose'. "You shall behold" according to sight. In what? In the image of man, in those six characteristics that we previously discussed, and everything is in that verse. "...you shall behold..." is the first, of the hair; "out of all the people" is the second, of the brow; "able men" is third, of the face; "such as fear G‑d" is the fourth, of the eyes; "men of truth" is the fifth, of the lips; "hating unjust gain" is sixth, of the hands and their lines.

For all these are the signs by which we recognize men on whom the spirit of Wisdom rests. Yet Moses had no need of them, for as it is written: "And Moses chose able men out of all Israel". (18:25) For the Holy Spirit came to him and informed him. And through this he could see it all.

From where do we learn this? From the verse: "When they have a matter, they come ('he comes') to me". (18:16) It is not written 'they come', but "he comes." This is the Holy Spirit that came to him, and that is how he knew. Therefore, Moses had no need to observe and ponder all this, since he knew instantly.

Similarly, King Solomon also knew. He knew through his throne, for the Holy Spirit rested upon it. Shaking and fear overcame everyone who came near his throne. And he could judge them without witnesses. Since there were images in his throne, the image would knock if anyone approached with a falsehood, and King Solomon would know that he came with a lie. Because of this the fear of the throne fell upon all, and all were found righteous before him.
King Messiah will judge by the fragrance...
King Messiah will judge by the fragrance, as it is written: "and his delight ('smell') shall be in the fear of G‑d; and he shall not judge after the sight of his eyes...". (Isaiah 11:3) And these three judged the world without witnesses and without warning. The rest of the world must judge by word of witnesses and by word of the Torah. It is incumbent upon those who are wise in these images to warn people and give them succor, and to heal them. Happy are they in this world, and happy are they in the World to Come.