Second Book of Paralipomenon (Author Compiled by Isaias and Esdras from records of Nathan, Gad, Addo, Ahias, Jehu and others.)
21:7noluit autem Dominus disperdere domum David propter pactum quod inierat cum eo et quia promiserat ut daret illi lucernam et filiis eius omni tempore
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.