'Posterity' in the Bible

“Say to the Israelites, ‘If any one of you or of your descendants becomes [ceremonially] unclean because of [touching] a dead body or is on a distant journey, he may, however, observe the Passover to the Lord.

All the offerings of the holy things, which the Israelites offer to the Lord I have given to you and to your sons and your daughters with you as a continual allotment. It is an everlasting covenant of salt [that cannot be dissolved or violated] before the Lord to you and to your descendants with you.”