How is our faith? Do we hold on to the promises of God, come what may? Do we live our lives as faithfully as we can? When we make mistakes (as everyone does, including Abraham, Isaac, Jacob and Joseph) do we repent? Or do we justify those mistakes?
This chapter of Hebrews begins with "Faith is the substance of things hoped for, the evidence of things unseen." Faith is based on something unseen. We don't need to have proof because we have promises. We so often can get wrapped up in the thing of this world, the messages the world gives us - all of them calling us to abandon our faith. It's so easy to get wrapped up in the day to day musings of the world... the state of the economy, what the leadership of our country is doing, injustices around the world and wonder... where is God? or even Does God exist?
It isn't until we seek God and find our own experiences of God that our faith will be strong enough to withstand the onslaught of doubt that naturally can come from being in the world. But just as Abraham, Isaac, Jacob and Joseph were "strangers and foreigners" so are we. We are in the world but we are called to be separate from it - at least to a degree. We live in the world to be the influence of the Kingdom of God on earth, but we must resist the temptations of doubt that will naturally bombard us. Instead, we must hold to the promises we've been given through Jesus Christ and understand that while we may not have seen the fruits of those promises, we, like those faithful ancestors before us, hold on to the promises of God through our Faith.