O house of Jacob - This is a direct address, or exhortation, of the prophet to the Jews. It is made in view of the fact that God had gracious purposes toward them. He intended to distinguish them by making them the source of blessings to all nations. As this was to be their high destiny, he exhorts them to devote themselves to him, and to live to his honor. The word “house” here means the “family, or nation.” The phrase is applied to the Jews because their tribes were descended from the twelve sons of Jacob.
Let us walk - Let us “live.” The word “walk” is often used to denote human life or conduct; compare Isaiah 2:3; Romans 6:4; Romans 8:1; 1 Corinthians 5:7; Galatians 6:16, ...
In the light of the Lord - The sense of this is: Let us obey the commandments of Yahweh; or, as the Chaldee expresses it, ‘Let us walk in the doctrine of the law of the Lord.’ The idea may be thus expressed: ‘Let us not walk in the darkness and error of sin and idolatry, but in the light or instruction which God sheds upon us by his law. He teaches us what we should do, and let us obey him.’ “Light” is often, in the Scriptures, thus put for instruction, or teaching; compare the note at Matthew 4:16; note at John 1:4; also, note at Ephesians 5:8.