First Book of Kings (Author Compiled by Isaias from records of Samuel, David, Nathan, and Gad.)
29:8dixitque David ad Achis quid enim feci et quid invenisti in me servo tuo a die qua fui in conspectu tuo usque in diem hanc ut non veniam et pugnem contra inimicos domini mei regis
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.