….for the Spirit of God shows to us hidden things, the knowledge of which cannot reach our senses: Promised to us is eternal life, but it is promised to the dead; we are assured of a happy resurrection, but we are as yet involved in corruption; we are pronounced just, as yet sin dwells in us; we hear that we are happy, but we are as yet in the midst of many miseries; an abundance of all good things is promised to us, but still we often hunger and thirst; God proclaims that he will come quickly, but he seems deaf when we cry to him. What would become of us were we not supported by hope, and did not our minds emerge out of the midst of darkness above the world through the light of God’s word and of his Spirit? Faith, then, is rightly said to be the subsistence or substance of things which are as yet the objects of hope and the evidence of things not seen. Augustine sometimes renders evidence “conviction,” which I do not disapprove, for it faithfully expresses the Apostle’s meaning: but I prefer “demonstration…”
–John Calvin, from his Commentary on Hebrews (Hat tip: GB)