Hebrews 11:11,12 - She considered Him faithful

11:11

Attention now turns briefly to Sarah. Sarah was barren and well past child bearing age, yet she gave birth to Isaac. She "received power to conceive offspring". "Since she considered the One who had promised was faithful". Now if we look at Gen 18:10-15 this was not a simple matter, for Sarah initially laughed at God's promise, and earlier it was Sarah who came up with the idea of Abraham sleeping with the servant girl. If we find it difficult to believe something we should not despair, for God can change our doubt to faith.

11:12

Now the Israelites knew they existed and that they had descended from Abraham. And that one man was "as good as dead", i.e. he could not have children and was old. Yet according to God's promise, he had numerous descendants. God's plans are based on His abilities, not on ours. They are based on faith.