Faith is the substance [hupostasis] of things hoped for, the assurance of things unseen.
In the first chapter of Jean-Pierre de Caussade's The Sacrament of the Present Moment he writes about three very ordinary people living hard, mundane lives. But God has given them promises. These promises place hope in their hearts, which shines a light on the dark circumstances surrounding them. They begin to view the world sub specie aeternitatis, through the lens of heaven.
De Caussade writes:
"What do they discern beneath the seemingly everyday events which occupy them? What is seen is similar to what happens to the rest of us. But what is unseen, that which faith discovers and unravels, is nothing less than God fulfilling his might purpose." (3)
In Hebrews 11: 1 "faith" is an ontological reality (a "substance") that transcends empirical realities. When we live by faith we see the ongoing activity of God and his kingdom that is "unseen" by our physical senses, and therefore is not contingent on our physical circumstances. Where one person sees a failing marriage, we see a restored marriage and point people in that direction. Where one person fatalistically sees doom and gloom, we see promise and hope. In this way faith has "substance" now, and we make purchases today that are grounded in our real, unseen hope in Christ.
Today, I am praying to see the unseen realities of God.