God's Children by God's Promises
Our God is a God of promises. He characteristically works by making and fulfilling promises. We are His children. We are children of promise. We were birthed spiritually into God's family through faith in His promises. Two sons of Abraham (Ishmael and Isaac) provide a vivid contrast that attests our sonship by promise.
God had promised to make Abraham a mighty nation, through which would come the Messianic seed that would bless all nations. "I will make you a great nation…and in you all the families of the earth shall be blessed" (Genesis 12:1-2). Yet, the years passed by, and Abraham was still without a son. Eventually, he implied to God that his servant would have to be the beginning of this promised seed. "Look, You have given me no offspring; indeed one born in my house [Eliezer, his servant] is my heir!" (Genesis 15:3). However, the Lord clarified His promise to give Abraham a true son, sired from his own body. "This one shall not be your heir, but one who will come from your own bodyshall be your heir" (Genesis 15:4). As time passed, the aging couple decided that they would have to come up with another alternative for God. "Now Sarai, Abram's wife, had borne him no children…So Sarai said to Abram, 'See now, the LORD has restrained me from bearing children. Please, go in to my maid; perhaps I shall obtain children by her.' And Abram heeded the voice of Sarai. So he went in to Hagar, and she conceived" (Genesis 16:1-2, 4). Thus, Ishmael was born as the result of Abraham's and Sarah's ingenuity: "But he who was of the bondwoman was born according to the flesh."
Thereafter, the Lord reiterated His promise of a son. "My covenant I will establish with Isaac, whom Sarah shall bear to you at this set time next year" (Genesis 17:21). As God promised, so He did. "And the LORD visited Sarah as He had said, and the LORD did for Sarah as He had spoken" (Genesis 21:1). Thus, Isaac was birthed as a result of God's promises. This is a picture of the only possible way that we could ever have become God's children, by His fulfilling of His promises."Now we, brethren, as Isaac was, are children of promise."
