Then thou spakest in vision - Or, by a vision. See this word explained in the notes at Isaiah 1:1. The meaning is, that God had spoken this by means of visions, or by communications made to his people by the prophets. This “vision” was especially made known to Nathan, and through him to David. See 2 Samuel 7:4-17. The substance of what is here said is found in that passage in Samuel. In 2 Samuel 7:17, it is expressly called a “vision.”
To thy holy one - The vision was addressed particularly to David, but was made through him to the people of Israel. The ancient versions render this in the plural, as referring to the people of Israel. The Hebrew is in the singular number.
I have laid help upon one that is mighty - I have so endowed him that he shall be the protector and defender of my people. He is qualified for the office entrusted to him, and in his hands the interests of the nation will be safe. This was not expressly said in the vision; but this was the substance of what was said. See 2 Samuel 7:9.
I have exalted one chosen out of the people - One not of exalted rank; one not descended from kings and conquerors; but one that had grown up among the people; one called from the ranks of common life; one chosen from among those engaged in humble occupations. In this way it was the more apparent that the power really came from God. Compare 2 Samuel 7:8; see also the notes at Psalms 78:70-72.