Deuteronomy 30:20

American Standard Version (ASV):
to love Jehovah thy God, to obey his voice, and to cleave unto him; for he is thy life, and the length of thy days; that thou mayest dwell in the land which Jehovah sware unto thy fathers, to Abraham, to Isaac, and to Jacob, to give them.

King James Version (KJV):
That thou mayest love the LORD thy God, [and] that thou mayest obey his voice, and that thou mayest cleave unto him: for he [is] thy life, and the length of thy days: that thou mayest dwell in the land which the LORD sware unto thy fathers, to Abraham, to Isaac, and to Jacob, to give them.