NET
12 Be warned, my son, of anything in addition to them. There is no end to the making of many books, and much study is exhausting to the body.
Darby
12 And besides, my son, be warned by them: of making many books there is no end, and much study is a weariness of the flesh.
KJV
12 And further, by these, my son, be admonished: of making many books [there is] no end; and much study [is] a weariness of the flesh.