Reading tonight through the Volume on S. John in the newly released Logos Cambridge Greek Testament for Schools and Colleges http://www.logos.com/product/8528/cambridge-greek-testament-for-schools-and-colleges and found the following on Saint John : Towards the very end of his life, when he was so infirm that he had to be carried to church and was too weak to preach, he used often to say no more than this, ‘Little children, love one another.’ His hearers at last wearied of this, and said, ‘Master, why dost thou always say this?’ ‘It is the Lord’s command,’ he replied, ‘and if this alone is done, it is enough’ (Jerome, Comm. in Ep. ad Gal. VI. 10). Thought I should check the reference but it has nothing to link to 
it seems we have nothing in Logos format on the Commentary by Jerome on the Epistle to the Galatians. [:(]
Suggest we might ask Logos to consider St. Jerome’s Commentaries on Galatians, Titus, and Philemon
Translated by Thomas P. Scheck (Notre Dame Press)
http://undpress.nd.edu/book/P01404
