How to Preach to the Old Testament as a Pastor

In 2 Samuel 7, the promises revealed to Abraham and Samuel in Genesis 49 are called a covenant. There's connections elsewhere with other passages in the Old Testament like Psalm 72,. The Virgin giving birth and then the kingship of the Messiah in Isaiah 9. When I see a failure in a king or a victory in virtue of a king in the Old testament, would it be that ultimately we are being reminded not to put our hope in men Abraham failed? He lied, but there's one coming, you know, who will not lie.