“Now the acts of David the king, first and last, behold, they are written in the book of Samuel the seer, and in the book of Nathan the prophet, and in the book of Gad the seer,”
King James Version (KJV)
29:29 The book - In the chronicles of the kingdom, which were writtenby Nathan and Gad, who were not only prophets, but historiographersout of which either they or some other prophets took by the direction ofGod's spirit such passages, as were most important and useful for thechurch in succeeding ages.