Revelation given through Joseph Smith the Prophet, at Kirtland, Ohio, March 9, 1833. The Prophet was at this time engaged in the translation of the Old Testament. Having come to that portion of the ancient writings called the Apocrypha, he inquired of the Lord and received this instruction.

1–3, The Apocrypha is mostly translated correctly but contains many interpolations by the hands of men that are not true; 4–6, It benefits those enlightened by the Spirit.

1 Verily, thus saith the Lord unto you concerning the Apocrypha—There are many things contained therein that are true, and it is mostly translated correctly;
Note: It was common knowledge that Maccabees was true history.
The books of 1 and 2 Maccabees in the biblical Apocrypha provide primary historical records of the 2nd-century BCE Jewish revolt against the Seleucid Empire and the origin of Hanukkah. While 1 Maccabees offers a sober, near-contemporary military chronicle, 2 Maccabees emphasizes theological framing, martyrdom, and divine intervention.

2 There are many things contained therein that are not true, which are interpolations by the hands of men.
Note: It was common knowledge that the apocrypha contained fiction.
The biblical Apocrypha contains historical and chronological inaccuracies—such as misidentifying King Nebuchadnezzar as an Assyrian ruler in Judith and condensing extended lifespans in Tobit—leading Protestants and Jewish authorities to reject them as non-canonical, while Catholic and Orthodox traditions view them as deuterocanonical scripture.

3 Verily, I say unto you, that it is not needful that the Apocrypha should be translated. 4 Therefore, whoso readeth it, let him understand, for the Spirit manifesteth truth; 5 And whoso is enlightened by the Spirit shall obtain benefit therefrom;
Note: The Holy Spirit will testify of Jesus Christ.
“But when the Helper comes, whom I shall send to you from the Father, the Spirit of truth who proceeds from the Father, He will testify of Me. And you also will bear witness, because you have been with Me from the beginning.” John 15:26-27

6 And whoso receiveth not by the Spirit, cannot be benefited. Therefore, it is not needful that it should be translated. Amen.
Note: The Holy Spirit will testify of Jesus Christ.
But he, being full of the Holy Spirit, gazed into heaven and saw the glory of God, and Jesus standing at the right hand of God, and said, “Look! I see the heavens opened and the Son of Man standing at the right hand of God!” Acts 7:55-56