According to Donl Peterson, Moroni felt impressed to include excerpts from a discourse of his father (Moroni 7). The last few verses of his sermon are quite similar to Paul's great sermon on faith, hope, and charity (see 1 Corinthians 13:4-7). It is logical to conclude, because these two sermons contain similar wording, that both were based upon a great sermon given by the Savior in his ministries among these two branches of the house of Israel. Moroni, too, was fond of this theme. In his own writings he had previously referred to the need for faith, hope, and charity (see Ether 12:28-35). [H. Donl Peterson, Moroni: Ancient Prophet Modern Messenger, p. 65]
“Charity Suffereth Long and is Kind and Envieth Not”
According to McConkie, Millet and Top, Mormon's language in Moroni 7 is unmistakably similar to Paul's language in his epistle to the Corinthians (1 Corinthians 13:4-7). Both Paul and Mormon described the charitable person as one who: (1) Suffers long, bears all things; (2) Is kind; (3) Envies not; (4) Is not puffed up, seeks not his own; (5) Is not easily provoked; (6) Thinks no evil; (7) Rejoices not in iniquity but rejoices in the truth; (8) Believes all things; (9) Hopes all things; (10) Endures all things.
Certainly both could have received independent revelations from the Lord on the same matter. In offering an alternative explanation, Elder Bruce R. McConkie said:
Both Paul and Mormon expounded with great inspiration about faith, hope, and charity, in many verses using the same words and phrases. If there is any difference between them it is that Mormon expounds the doctrines more perfectly and persuasively than does Paul. It does not take much insight to know that Mormon and Paul both had before them the writings of some Old Testament prophet on the same subjects. ("The Doctrinal Restoration," in The Joseph Smith Translation: The Restoration of Plain and Precious Things, p. 18)
[Joseph F. McConkie, Robert L. Millet, Brent L. Top, Doctrinal Commentary on the Book of Mormon, Vol. IV, pp. 343-345] [See the commentary on Moroni 10:8-17]