John Chrysostom

"By Faith, Isaac blessed Jacob and Esau concerning things to come" (and yet Esau was the elder; but he puts Jacob first for his excellence). Seest thou how great was his Faith? Whence did he promise to his sons so great blessings? Entirely from his having faith in God.

Homily on Hebrews 26 ↗

Theophylact of Ohrid

How could he have promised his sons so many good things, himself living in a foreign land, if he did not believe that God would grant what was promised? What does "concerning things to come" mean? Either the good things of the age to come, for they knew about the resurrection and these blessings were understood by them, or the good things on this earth, which they themselves or their descendants were to receive. …

Commentary on Hebrews ↗

Oecumenius

"By faith, Isaac blessed Jacob and Esau concerning things to come." From where were such good things promised to his sons, if he did not believe that God would give the promises? And what is it, concerning things to come? Or concerning what is to happen to them, or concerning what is to be given to their offspring. For neither did they themselves enjoy the promise. Jacob, however, is first named because of his virtue.

The Pseudo-Oecumenian Catena on Hebrews ↗

Thomas Aquinas

607. – Above, the Apostle gave an example of Abraham's faith; here he gives the example of the faith of Isaac, Jacob and Joseph: and first of Isaac's faith. He says, therefore, that by faith of things to come, i.e., of things that extended into the future, Isaac blessed Jacob and Esau. Or, he blessed them for things to come; or with a blessing which extended to the future. For his words had efficacy from God's power alone. Through this blessing the younger ruled the older. …

Commentary on Hebrews ↗