The Conferences Of John Cassian by John Cassian
Chapter IX. How it is often better to break one's engagements than to fulfil them.
And both these points are very clearly shown by the cases of S. Peter the Apostle and Herod. For the former, because he departed from his expressed determination which he had as it were confirmed with an oath saying |Thou shalt never wash my feet,| gained an immortal partnership with Christ, whereas he would certainly have been cut off from the grace of this blessedness, if he had clung obstinately to his word. But the latter, by clinging to the pledge of his ill-considered oath, became the bloody murderer of the Lord's forerunner, and through the vain fear of perjury plunged himself into condemnation and the punishment of everlasting death. In everything then we must consider the end, and must according to it direct our course and aim, and if when some wiser counsel supervenes, we see it diverging to the worse part, it is better to discard the unsuitable arrangement, and to come to a better mind rather than to cling obstinately to our engagements and so become involved in worse sins.