Come … let us walk: Walking in God's light (his revelation) leads to a glorious role in his kingdom (see Isaiah 60:1; 1 John 1:7). God is the only light that defeats the darkness of sin and evil (Isaiah 9:2).
People cannot create this light on their own (Isaiah 59:9). They must walk in the light God provides, trusting him and obeying his will (Isaiah 50:10).
The phrase house of Jacob refers to Israel's special historic relationship with the Lord and their history of sin and rebellion (see Isaiah 14:1; 48:1).