Abraham is used as the backdrop. He had some 'audacious' promises that were given to Him. If you follow one of the 'lectionary' readings; this may have been your reading last week. When he heard the promises, he trusted God and set out.
For those who do not know all the geneology; from Abraham's son (Issac) came the Israelites. Six hundred +/- years later, they received the promised land. Today, you and I are "blessed" by Jesus, a son of Abraham.
Give me the assurance of all your wonderful promises.