St. Alphonsus Maria de Liguori (1696–1787)
Alphonsus Liguori was a lawyer who left the bar after losing a case he had prepared perfectly, a bishop who resigned his see, and the most published Catholic author of his age. He wrote for people who would never read a theologian: in plain Italian, with the argument in front and the ornament left off. The Church made him a Doctor in 1871.
These seven volumes come from the Italian, with Scripture in the Douay-Rheims and his own paragraph numbers kept throughout. The Sunday sermons are free to read here entire, being an older English restored rather than a new translation; the volumes translated afresh open their front matter and their first chapter. Three are still in proof.
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A Rule of Life — the daily order he gave ordinary people, drawn from these volumes and cut to a single sheet you can print: the morning offering, his method of mental prayer, the prayers for through the day, and the three Acts for the evening.

Volume I
His complete instruction for ordinary people on the Ten Commandments and the Sacraments, with a short catechism in questions and answers, a rule of Christian life, and a discourse to a confraternity.
23 chapters

Volume II
The full course of fifty-seven sermons for the Sundays and great feasts of the year, the most widely preached body of Catholic sermons ever written, with his spiritual writings and the Brief Practice for Perfection.
57 sermons and 4 spiritual writings

Volume III
His treatise on charity, written around St. Paul's account of love in the thirteenth chapter of First Corinthians: the book Alphonsus himself said he would keep if he could keep only one.
18 chapters

Volume IV
The first part of his great work on the Blessed Virgin: the Salve Regina expounded clause by clause, with the prayers that close it.
11 chapters

Volume V
The second part: discourses for the feasts of Mary through the year, her sorrows, her virtues, and the traditional devotions.
15 chapters

Volume VI
Written in his seventy-first year against the unbelief pouring out of Enlightenment Europe, and answering the materialists, the deists, and the adversaries of the Church in turn. In English for the first time.
40 chapters

Volume VII
His defense of the Council of Trent, taken session by session against the Reformers. Last in English in 1846, and translated here afresh from the Italian.
16 sessions and treatises