persevere vs progress in virtue

Are we persevering in our virtue or progressing in it?

let us clearly define in what this progress consists. A paradox of the prudent and spiritual St. Theresa will help us to make our meaning clear: “Since I have been prioress, burdened with many duties and obliged to travel a great deal, I commit very many more faults. And yet, as I struggle generously and spend myself for God alone, I feel that I am getting closer and closer to Him.” Her weakness shows itself much more than it did in the peace and quiet of the cloister. The saint is aware of this, but does not let it cause her any worry. The completely supernatural generosity of her devotion to duty and her greatly increased efforts in the spiritual combat make up for everything by providing an opportunity for victories which largely outweigh the surprise faults of a weakness that was always there, but formerly only in a latent state. Our union with God, says St. John of the Cross, resides in the union of our will with His, and is measured entirely by that union. Instead of taking the mistaken view of spirituality which would see no possibility of progress in divine union except in tranquility and solitude, St. Theresa judges that it is rather an activity truly imposed on us by God and carried out under the conditions laid down by His will, which, by nourishing her spirit of sacrifice, her humility, her abnegation, her ardor and devotion for the Kingdom of God, serves to increase the intimate union of her soul with Our Lord, who lives in her and gives life to her work; and it is thus that she advances on the road to sanctity.

Sanctity, as a matter of fact, consists above all in charity, and any apostolic work that is worthy of the name is simply charity in action. Probatio amoris, says St. Gregory, exhibitio est operis. The proof of love is in works of self-denial, and this proof of devotion is something God demands of all His workers.

“Feed my lambs, feed my sheep,” is the form of charity which Our Lord demands of the apostle as a proof of the sincerity of his repeated protestations of love.