from The Homilies of St. John Chrysostom on the Epistle to the Hebrews
What is "the hope set before us" (Hebrews 6:18)? From these [past events] (he says) we conjecture the future. For if these came to pass after so long a time, so certainly the others will. So that the things which happened in regard to Abraham give us confidence also concerning the things to come.
"Which [hope] we have as an anchor of the soul both sure and steadfast, and which entereth into that within the veil: whither the forerunner is for us entered, even JESUS, made High Priest forever after the order of Melchisedec." (Hebrews 6:19-20)
He shows, that while we are still in the world, and not yet departed from [this] life, we are already among the promises. For through hope we are already in heaven. He said, "Wait; for it shall surely be." Afterwards giving them full assurance, he says, "nay rather by hope." And he said not, "We are within," but 'It hath entered within,' which was more true and more persuasive. For as the anchor, dropped from the vessel, does not allow it to be carried about, even if ten thousand winds agitate it, but being depended upon makes it steady, so also does hope.
And see how very suitable an image he has discovered: For he said not, Foundation; which was not suitable; but, "Anchor." For that which is on the tossing sea, and seems not to be very firmly fixed, stands on the water as upon land, and is shaken and yet is not shaken. For in regard to those who are very firm, and philosophic, Christ with good reason made that statement, saying, "Whosoever hath built his house on a rock." (Matt. vii. 24.)