From the beginning down through the dispensations, God has used angels as His emissaries in conveying love and concern for His children.
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Usually such beings are not seen. Sometimes they are. But seen or unseen they are always near. Sometimes their assignments are very grand and have significance for the whole world. Sometimes the messages are more private. Occasionally the angelic purpose is to warn. But most often it is to comfort, to provide some form of merciful attention, guidance in difficult times.

-Elder Jeffrey R. Holland, "The Ministry of Angels," October 2008 General Conference