Missionaries are wingless, mortal angels who are sent from God just as literally as those who abide with Him in his royal courts above. Many pray for an angelic visitation, and get a home teaching visit instead. The Lord doesn't need to send angels to do things that his mortal servants are capable of doing for him. He doesn't need to send angels with trumpets to declare salvation to the wicked of the world. Rather, he uses Mormon missionaries to do this for him. Elder Robert L. Simpson tells a story of how one man was visited by this kind of angel:
"[Elder Simpson] described an Englishman working in his flower bed on a Saturday morning. A voice from behind asked him: 'Sir, do you love the Lord?' The man turned around, 'fully expecting to see an angel standing there; instead there were two angels, two Mormon missionaries,' said Elder Simpson. 'It was all so simple, so genuine. It was an approach that the Savior might have used.'" (Church News, 4/15/84)