Missions is Not Sacrifice- so says David Livingston?

"When David Livingstone visited Cambridge University on December 4, 1857, he made an earnest appeal for that continent (Africa), which was then almost wholly an unoccupied field. His words, which were in a sense his last will and testament for college men, as regards Africa, may well close this book:

"For my own part, I have never ceased to rejoice that God has appointed me to such an office. People talk of the sacrifice I have made in spending so much of my life in Africa. Can that be called a sacrifice which is simply paid back as a small part of a great debt owing to our God, which we can never repay? Is that a sacrifice which brings its own blest reward in healthful activity the consciousness of doing good, peace of mind, and a bright hope of a glorious destiny hereafter? Away with the word in such a view, and with such a thought! It is emphatically no sacrifice. Say rather it is a privilege. Anxiety, sickness, suffering, or danger, now and then, with a foregoing of the common conveniences and charities of this life, may make us pause, arid cause the spirit to waver, and the soul to sink, but let this only be for a moment. All these are nothing when compared with the glory which shall hereafter be revealed in and for us. I never made a sacrifice."

("The Glory of the Impossible”, Samuel Zwemer. “Perspectives on the world Christian Movement", 1999, William Carey Library, Pasadena California . Pg 315)