Midrash sur L’Ecclésiaste 1:18

R. Acha b. Chanina said: "Had not Israel committed any crimes, they would have had no other Scriptures than the five books of the Torah (the law) and the book of Joshua, [which last is indispensable,] because therein is recorded how the land was distributed among Israel, [but the remainder was added,] as it is said (Ecc. 1, 18) Since there is much wisdom [of all the prophetic books,] there is a sign that it occasioned much vexation."