Alma 13:21-25; Moro. 7:30-31; 2 Ne. 32:3; Heb. 13:1-2; Teachings of the Prophet Joseph Smith, p. 191; refer in this text to Alma 3:26-27
“It is contrary to the law of God for the heavens to be opened and messengers to come to do anything for man that man can do for himself… . You cannot point to anywhere in the scriptures where a messenger has come from the heavens and bestowed upon man something man could do for himself, but angels have come and told men what to do and sent men to do it.” (Joseph Fielding Smith, Doctrines of Salvation, 1:196)
“The Lord is here with us, not in person, but his angels are around us, and he takes cognizance of every act of the children of men, as individuals and as nations. He is here ready by his agents, the angels, … to bring most perfect and absolute deliverance unto all who put their trust in him, when they are ready to receive it… . What is the difference between Saints of God and an angel of God? One is clothed upon with mortality, the other has passed through mortality and has received the celestial glory of our Heavenly Father, and is free from the contaminating influences of sin that we have to contend with… . When the Lord commands those invisible beings, shall I say, those who have had their resurrection? yes, millions and millions more than the inhabitants of this earth, they can fight your battles.” (Discourses of Brigham Young, pp. 41-42)