What God says to be true, will always be true, no matter what we see or what we feel. Abraham walked in and trusted what God said to be true about him; he would be the father of many nations. As Christians, we can have the same confidence when it comes to who God says that we are and we can approach the throne of grace with boldness because of our new identity through the blood of Christ.
"No longer shall your name be called Abram, but your name shall be Abraham, for I have made you the father of a multitude of nations. I will make you exceedingly fruitful, and I will make you into nations, and kings shall come from you." Genesis 17:5-6