“The word προβολή properly means anything which proceeds or is sent forth from the substance of another, as the fruit of a tree or the rays of the sun. In Latin, it is translated by prolatio, emissio, or editio, or what we now express by the word development. In Tertullian’s time, Valentinus had given the term a material signification. Tertullian, therefore, has to apologize for using it, when writing against Praxeas, the forerunner of the Sabellians” (Newman’s Arians, ii. 4; reprint, p. 101).