Tobit 4:12-13

12 Beware of all whoredom, my son, and chiefly take a wife of the seed of thy fathers, and take not a strange woman to wife, which is not of thy father's tribe: for we are the children of the prophets, Noe, Abraham, Isaac, and Jacob: remember, my son, that our fathers from the beginning, even that they all married wives of their own kindred, and were blessed in their children, and their seed shall inherit the land.
13 Now therefore, my son, love thy brethren, and despise not in thy heart thy brethren, the sons and daughters of thy people, in not taking a wife of them: for in pride is destruction and much trouble, and in lewdness is decay and great want: for lewdness is the mother of famine.
The King James Version is in the public domain.