Patristic Wisdom: Looking to Sunday

2 Thess., Walters Ms. W.533

But we are bound to give thanks to God always for you, brethren beloved by the Lord, because God from the beginning chose you for salvation through sanctification by the Spirit and belief in the truth, to which He called you by our gospel, for the obtaining of the glory of our Lord Jesus Christ.  Therefore, brethren, stand fast and hold the traditions which you were taught, whether by word or our epistle.  (2 Thess 2:13-15)

We shall sing the praises of the Source of the good things for granting you salvation and giving you a share in the Holy Spirit so that in your case as well He may be celebrated by all.  Keep as the norm of doctrine the words offered you by us, which we preached to you when present and wrote when absent.

Then he confirms the teaching with a prayer:
May He who loved those who hate Him, called those who are hostile, and gave them the hope of future goods strengthen you in the faith, so that you may be conspicuous for good works and similar deeds.

Theodoret of Cyrus, Commentary on 2 Thessalonians

How [were you chosen] unto salvation?  By sanctifying you through the Spirit.  For these are the things that are the efficient causes of our salvation.  It is not of works, not of righteous deeds, but through belief of the truth.… If Christ considers our salvation His glory, this too is no little thing.  For it is the glory of the Friend of man that they who are saved should be many.  Great then is our Lord, if the Holy Spirit so desires our salvation.  Why did he not say faith first?  Because even after sanctification we have a need of much faith that we may not be shaken.  Do you see how He shows that nothing is of themselves, but all of God?

John Chrysostom, Homilies on 2 Thessalonians, IV