The so-called lost books of the Bible are those documents that are mentioned in the Bible in such a way that it is evident they are considered authentic and valuable, but that are not found in the Bible today. Sometimes called missing scripture, they consist of at least the following:
book of the Wars of the Lord (Num. 21: 14); book of Jasher (Josh. 10: 13; 2 Sam. 1: 18); book of the acts of Solomon (1 Kgs. 11: 41); book of Samuel the seer (1 Chr. 29: 29); book of Gad the seer (1 Chr. 29: 29); book of Nathan the prophet (1 Chr. 29: 29; 2 Chr. 9: 29); prophecy of Ahijah (2 Chr. 9: 29); visions of Iddo the seer (2 Chr. 9: 29; 2 Chr. 12: 15; 2 Chr. 13: 22); book of Shemaiah (2 Chr. 12: 15); book of Jehu (2 Chr. 20: 34); sayings of the seers (2 Chr. 33: 19); an epistle of Paul to the Corinthians, earlier than our present 1 Corinthians (1 Cor. 5: 9); possibly an earlier epistle to the Ephesians (Eph. 3: 3); an epistle to the Church at Laodicea (Col. 4: 16); and some prophecies of Enoch, known to Jude (Jude 1: 14).
To these rather clear references to inspired writings other than our current Bible may be added another list that has allusions to writings that may or may not be contained within our present text, but may perhaps be known by a different title; for example, the book of the covenant (Ex. 24: 7), which may or may not be included in the current book of Exodus; the manner of the kingdom, written by Samuel (1 Sam. 10: 25); the rest of the acts of Uzziah written by Isaiah (2 Chr. 26: 22).
The foregoing items attest to the fact that our present Bible does not contain all of the word of the Lord that he gave to his people in former times, and remind us that the Bible, in its present form, is rather incomplete.
Many years after the time of the Apostles, there was a translation of the OT from ancient Hebrew to koine Greek made by a group of Jews. During this translation they edited a letter here, a word there, to carefully eliminate Jesus as Messiah. We know this because of certain passages such as the one where James quotes Amos (Acts 15:14-17) yet the different rendering of Amos done by the Jews in their 'special translation' states the passage differently with just the change of one Hebrew letter or word! When James offered his rendering of Amos, learned Pharisees present at that Jerusalem Council would have objected strenuously had James quoted incorrectly. Thereby we may be assured that James quotes the 'unedited' version of Amos. [See footnote#2 in Scofield's Standard Reference Bible on Amos 9:12] But ought that be used to sow doubt that the Bible accomplishes that which God intends for His Word? Not at all, yet you use issues of incompleteness and inaccuracy to sow doubt into which you hope to spread the seeds of Mormonism. It is getting disgusting to behold as you serve this divisive spirit so cunningly and --it is my prayer-- so 'inadvertently'.