Genesis 15:4
And, behold, the word of the LORD came to him, saying, This shall not be your heir; but he that shall come forth out of your own bowels shall be your heir.
Nave's Topical Index—AKJV

Genesis 21:10
Why she said to Abraham, Cast out this female slave and her son: for the son of this female slave shall not be heir with my son, even with Isaac.
Nave's Topical Index—AKJV