John Piper writes this, about David Livingstone:
David Livingstone was born March 19, 1813. He gave his life to serve Christ in the exploration of Africa for the sake of creating access to the gospel. He was the first European to cross the width of Africa, and the first to set his eyes on Victoria Falls, which he named after his queen. He also laid his eyes on the horrors of the East African slave trade, and devoted himself with passion as an abolitionist.
Many doubted Livingstone’s sincerity as a missionary, since he spent so much of his time exploring. But his own perspective was clear: “As for me, I am determined to open up Africa or perish.” He said, “The end of the exploration is the beginning of the enterprise.”
A year before he died in 1873, he wrote in his journal on his 59th birthday, “My birthday! My Jesus, my King, my Life, my All. I again dedicate my whole self to Thee.”
Here is what he said to the Cambridge students, on December 4, 1857, about what it had meant for him to leave his homeland of England:
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. . . . 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, and 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 be revealed in and for us.
I never made a sacrifice.