St Isaac the Syrian lived in the seventh century and wrote in Syriac. He was made bishop of Nineveh, gave up the office after about five months, and withdrew to live as a hermit, where he wrote his homilies. By the end of his life he was nearly blind.
His writings were translated into Greek by two monks of the monastery of St Sabbas near Jerusalem, and from there they spread through the whole Orthodox world. Monks and lay people have read him ever since. The Orthodox Church keeps his memory on January 28.
St Isaac writes about the inner life with great tenderness: about prayer and stillness, about tears and repentance, and about humility. He is best known for his teaching on the merciful heart, a heart that burns with love for the whole creation, for people, for animals, even for those who do harm.
His homilies are not a system to be read straight through in a week. They are best taken slowly, a few pages at a time, as a monk would read them.