Let thy hand be upon the man of thy right hand - Luther renders this, “Let thy hand guard the folks of thy right hand, and the people whom thou hast powerfully chosen.” The right hand is the place of honor; and the phrase “the man of thy right hand” means one who occupies such a position of honor. The phrase “Let thy hand be upon” is ambiguous. It may denote either favor or wrath; let it be upon him either to protect him, or to punish him. The connection, however, evidently demands the former interpretation, for it is in reference to the “man whom God had made strong for himself.” The allusion is either
(a) to some individual man whom God had raised up to honor, as a prince or ruler of the people; or
(b) to the people as such - as Luther understands it.
Most probably the former is the correct interpretation; and the prayer is, that God would interpose in behalf of the ruler of the people - the king of the nation - whom he had exalted to so high honor, and whom he had placed in such a position of responsibility; that he would now endow him properly for his work; that he would give him wisdom in counsel, and valor in battle, in order that the nation might be delivered from its foes. It is, therefore, a prayer for the civil and military ruler of the land, that God would give him grace, firmness, and wisdom, in a time of great emergency. Prof. Alexander strangely supposes that this refers to the Messiah.
Upon the son of man - This means simply man, the language being varied for the sake of poetry. Compare the notes at Psalms 8:4. It is true that the appellation “the Son of man” was a favorite designation which the Lord Jesus applied to himself to denote that he was truly a man, and to indicate his connection with human nature; but the phrase is often used merely to denote a man. Here it refers to the king or civil ruler.
Whom thou madest strong for thyself - The man whom thou hast raised up to that exalted station, and whom thou hast endowed to do a work for thee in that station. A magistrate is a servant and a representative of God, appointed to do a work for him - not for himself. See Romans 13:1-6.