The Conferences Of John Cassian by John Cassian
Chapter XXVII. A question whether the saying: |I have sworn and am purposed| is opposed to the view given above.
Germanus: So far as this consideration is concerned which has been clearly and fully treated of, a monk ought never to determine anything for fear lest he turn out a breaker of his word or else obstinate. And what then can we make of this saying of the Psalmist: |I have sworn and am purposed to keep Thy righteous judgments?| What is |to swear and purpose| except to keep one's determinations fixedly?