In Genesis 2:24 the narrator declares that a man leaves his father and mother and clings to his wife and they become one flesh. There is a profound act of letting go required before something new and fruitful is made possible. The leaving and cleaving one becomes one flesh with his wife.
Like anyone who experiences this need to cleave to another, the old securities and familiarities need to be relinquished to create the possibility of newness and new fruitfulness.
Abraham’s journey from his father’s house has all the echoes of a search for a bride and the creation of new oneness with the fruitfulness that we take for granted must follow.
Only this time the couple are barren, and they travel solely with the promise of God and the hope, perhaps, that his word can be relied on, the make them into a great population.