""A Commentary on the Te Deum: Chiefly from Ancient Sources"" is a book written by Alexander Penrose Forbes and published in 1850. The book is a detailed analysis of the Te Deum, a Christian hymn of praise that has been used in liturgical settings for centuries. Forbes draws heavily on ancient sources, including the writings of Church Fathers such as Augustine and Ambrose, to provide insight into the history and meaning of the hymn. The book includes...