Second Book of Kings (Author Compiled by Isaias from records of Samuel, David, Nathan, and Gad.)
Chapter 24
17dixitque David ad Dominum cum vidisset angelum caedentem populum ego sum qui peccavi ego inique egi isti qui oves sunt quid fecerunt vertatur obsecro manus tua contra me et contra domum patris mei
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.