(quote from RealReality.org/Real_Faith_and_Reason_Vol_3_-_Scientia.pdf)

Hebrews 1:1 tells us faith is the substance of things hoped for. It’s the confidence in what we hope for. It’s the reality of what we hope for. It’s the assurance of what we hope for. The word translated as substance, confidence, assurance, or reality is also translated as phrases like “makes us sure,” “being sure,” or “a well-grounded assurance.” … This is a word that expresses something solid and real.

(end quote)