Let the Nations Be Glad! This is a classic book on the role of mission within the church. A must read.
The most exhilarating thought in the world is that God’s inexorable purpose is to display His glory in the mission of the church is virtually the same as His purpose to give His people infinite delight. p. 33-4.
He (Paul) was gripped by the OT purpose of God to bless all the nations of the earth (Gal. 3:8) and the be praised by all the peoples (Rom. 15:11), and to send salvation to the end of the earth (Acts 13:47), and to make Abraham the father of many nations (Ro. 4:17), and to be understood in every group where He is not known (Ro. 15:21). . . . His aim was not to reach as many Gentile individuals as he could but to reach as many unreached peoples as he could. This was Paul’s specific missionary vision. p. 195.
God’s focus: the gospel proclaimed to all the people groups of the world. This focus “undercuts ethnocentric pride and puts all peoples back upon his free grace rather than any distinctive of their own” p. 217.
It’s a humbling thing to discover that God does not choose our people group because of any distinctives of worth, but rather that we might double our joy in him by being a means of bringing all the other groups into the same joy. Humility is the flip side of giving God all of the glory. Humility means reveling in his grace, not our goodness. In pressing us on to all the peoples God is pressing us further into the humblest and deepest experience of his grace, and weaning us more and more from our ingrained pride. In doing this he is preparing for himself a people - from all the peoples - who will be able to worship him with free and white-hot admiration. p. 218