Many of our assignments in the Church are shared with companions. Ever since the Lord sent out His disciples two by two, companionships have advanced the work of the Kingdom. The Lord's law of witnesses requires that "in the mouth of two or three witnesses shall every word be established." When the grieving women came to the empty tomb that first glorious Easter morn, it was two heavenly messengers who declared, "He is not here, but is risen."
After the Lord's ascension from the Mount of Olives, two messengers bore testimony of the risen Lord. And both the Father and the Son together visited Joseph Smith to begin the glorious work of the Restoration. In bearing testimony and establishing truth, two are better than one.