James Henley Thornwell's sermon "The Sacrifice of Christ the Type and Model of Missionary Effort" in Volume 2 of his Collected Writings is something every missionary, every pastor, every Christian should read. In it, he reflects upon John 10:17-18, and Jesus' voluntary sacrifice for His people, and draws application from it for the church of Jesus in every age. What motivated and marked Jesus must motivate and mark His disciples: reverence for God's glory, pity for the misery of man, a willingness to suffer, and a hope of reward. There are so many quotes I could highlight, but I'll give you these two. Read the entire sermon this afternoon!
“Is there nothing in this spectacle of a world in ruins to stir the compassion of the Christian heart? Can we look upon our fellows, members of the same family, pregnant with the same instincts and destined to the same immortality, and feel no concern for the awful prospect before them? They are perishing, and we have the bread of life; they are famished with thirst, and we have the water of which if a man drink he shall never thirst; they are dead, and we have the Spirit of life. We have but to announce our Savior’s name, to spread the story of the Cross, and we open the door of hope to the multitudes that are perishing for lack of knowledge.” (432)
“When I consider the magnitude and grandeur of the motives which press upon the Church to undertake the evangelization of the world; when I see that the glory of God, the love of the Savior and pity for the lost all conspire in one great conclusion; when I contemplate our own character and relations as spiritual priests, and comprehend the dignity, the honor, the tenderness and self-denial of the office; and then reflect upon the indifference, apathy and languor which have seized upon the people of God; when I look to the heavens above me and the world around me, and hear the call which the wail of perishing millions sends up to the skies thundered back upon the Church with all the solemnity of a Divine commission; when a world says, Come, and pleads its miseries; when God says, Go, and pleads His glory, and Christ repeats the command, and points to His hands and His feet and His side – it is enough to make the stone cry out of the wall and the beam out of the timber to answer it.” (448)