Ezra 9:11-14

which You have commanded by Your servants the prophets, saying, ‘The land which you are entering to possess is a defiled land with the uncleanness of the peoples of the lands, through their repulsive acts which have filled it from one end to the other along with their impurity. So now do not give your daughters to their sons or take their daughters for your sons; and never seek their peace or their prosperity, so that you may be strong and eat the good things of the land and leave it as an inheritance to your children forever.’ And after everything that has come upon us for our evil deeds and for our great guilt, since You our God have punished us less than our wrongdoings deserve, and have given us survivors like these, shall we again break Your commandments and intermarry with the peoples who practice these repulsive acts? Would You not be angry with us to the point of total destruction, so that there would be no remnant nor survivor? [Deut 7:2-4]