that we may preserve unto them the words which have been spoken by the mouth of all the holy prophets - 1 Nephi 3:20

1 Nephi 3:19-20

And behold, it is wisdom in God that we should obtain these records, that we may preserve unto our children the language of our fathers;
And also that we may preserve unto them the words which have been spoken by the mouth of all the holy prophets, which have been delivered unto them by the Spirit and power of God, since the world began, even down unto this present time.
1 Nephi 3:19-20

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That they might set their hope in God, and not forget the works of God, but keep his commandments: Psalms 78:7

Psalms 78:5-7

For he established a testimony in Jacob, and appointed a law in Israel, which he commanded our fathers, that they should make them known to their children:
That the generation to come might know them, even the children which should be born; who should arise and declare them to their children:
That they might set their hope in God, and not forget the works of God, but keep his commandments:
Psalms 78:5-7

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