St. Francis de Sales had an “Augustinian cast of mind”, it has been said.
Certainly he respected this great doctor of the Church and chose the Rule of St. Augustine for the Visitation Order that he founded with St Jane de Chantal.
That is why we call St Francis de Sales our “holy Father” and St Augustine our “grandfather”.
St. Augustine had a preponderant influence on Francis de Sales.
He cites him numerous times in the Treatise, especially from his Confessions and the City of God.
What struck St. Francis, among others things,in the teachings of Augustine was the prevalence and power of love, especially the
love of God. Augustine certainly understood the role and importance
of reason in the act of faith.