This is one of the first insights in Messages from the Scriptures. It was originally posted at my publisher's blog (and of course, it can be found in the book itself).
Though they are away from their families, missionaries are not alone, for God has promised to be with them.
Behold, I will go before you and be your rearward; and I will be in your midst, and you shall not be confounded. (D&C 49:27)
The Lord said He would “send for many fishers” and “many hunters” to seek out the inhabitants of the earth and teach the gospel (Jeremiah 16:16). Paul admitted that in order to have preaching, missionaries must first be sent (see Romans 10:15). Sometimes “being sent” means separation, not just from one’s family and friends but also from one’s home and culture. Serving as a missionary can be difficult, but missionaries should not feel alone. In the latter days, Christ promised blessings to missionaries, saying, “The power of heaven [shall] come down among them; and I also will be in their midst” (3 Nephi 21:25). The same idea appears in Zenos’ allegory of the olive trees: “The Lord of the vineyard said unto them: Go to, and labor in the vineyard, with your might. . . . And it came to pass that the servants did go and labor with their mights; and the Lord of the vineyard labored also with them” (Jacob 5:71–72). In moments of discouragement, missionaries should remember that the Savior has promised to be with them.