Theodoret of Cyrus: Paul Habitually Predestinarian

He joined the phrase, Let us do this, if God permits, to the preceding phrase, Hence, leaving aside the account of Christ's beginning, let us move on to maturity: let us do it, if God permits - that is, Let us be zealous, let us desire, let us embrace every effort for maturity. Now, the apostle is accustomed to attribute everything to divine providence - hence his addition of if God permits; likewise in writing to the Corinthians he said, "I shall come to you, God willing."

- Theodoret of Cyrus (around A.D. 393 to around A.D. 457), Commentary on Hebrews, Chapter 6, in Theodoret of Cyrus, Commentary on the Letters of St. Paul, Volume 2, p. 159 (2001), Robert C. Hill translator.