12 In my youth when the desert walled me in with its solitude I was still unable to endure the promptings of sin and the natural heat of my blood; and, although I tried by frequent fasts to break the force of both, my mind still surged with [evil] thoughts. To subdue its turbulence I betook myself to a brother who before his conversion had been a Jew and asked him to teach me Hebrew. Thus, after having familiarised myself with the pointedness of Quintilian, the fluency of Cicero, the seriousness of Fronto and the gentleness of Pliny, I began to learn my letters anew and to study to pronounce words both harsh and guttural. What labour I spent upon this task, what difficulties I went through, how often I despaired, how often I gave over and then in my eagerness to learn commenced again, can be attested both by myself the subject of this misery and by those who then lived with me. But I thank the Lord that from this seed of learning sown in bitterness I now cull sweet fruits.
Source: Letters (New Advent)