Many people are surprised when I tell them that reading Calvin is some of the sweetest, most devotional stuff that I read in seminary...most of those people have never read Calvin and/or have a distorted view of who Calvin was in the first place. I absolutely LOVE John Calvin's writings, and to tell you the truth, wouldn't mind if seminary consisted of Greek, Hebrew, and Aramaic bible study, English bible study, and a study of The Institutes of the Christian Religion. But...its probably a good thing that I'm not the one who sets seminary curriculum.
Anyway, I read this passage a while back, and even though it isn't explicitly about world missions, it is its foundation; in fact, it is the foundation for all of Christian life. Calvin writes in Book III, ch. 18.6, 'On "treasures in heaven"',
"If what Christ says is true--"Where our treasure is, there resides our heart" [Matt. 6:21]...believers ought to see to it that, after they have learned that this life will soon vanish like a dream, they transfer the things they want truly to enjoy to a place where they will have life unceasing. We ought, then, to imitate what people do who determine to migrate to another place, where they have chosen a lasting abode. They send before them all their resources and do not grieve over lacking them for a time, for they deem themselves the happier the more goods they have where they will be for a long time. But if we believe heaven is our country, it is better to transmit our possessions thither than to keep them here where upon our sudden migration they would be lost to us."
The Institutes of the Christian Religion, p. 827
I pray that we (especially me!), as believers, can believe this...the truth that is at the center of all of Scripture: our King is bringing a kingdom that cannot be shaken! Therefore, for the believer, until the King appears, life is about establishing His kingdom through our time, money and prayers.