In March, Lord willing, I will be traveling to Zambia to teach a course on the book of Hebrews to sophomores at International Bible College. In the process of preparing materials for the course I was gathering information for a sidebar on Tertullian and read a great summary and evaluation of his life and ministry:
When one only sees his thought in all its greatness, in the end, it is precisely this greatness that is lost. The essential characteristic of a great theologian is the humility to remain with the Church, to accept his own and others’ weaknesses, because actually only God is all holy. We, instead, always need forgiveness.
Tertullian’s place in the pantheon of theologians is illustrated by some of the appellations given him: “the father of Latin theology”, “the father of ecclesiastical Latin”, etc. Tertullian gave us the word Trinity. He was the first to use “person” and “substance” in Trinitarian discussion. He was the first to refer to the church as “mother.” On estimate credits him with coining over 900 terms. Humanly speaking, Tertullian provided the language of orthodox.
Yet he left the church. Through a desire for more rigorous holiness, he left the church for the heretical fellowship of the Montanists.
This remains a constant temptation. Man is proud. It is easier to look down on others than to come down to help them. There are some who seem to be always exposing the sin of others or trumpeting their own righteousness. It must be a miserable struggle to decide which sin to engage in today. But take rest troubled soul: exalting in your own righteousness or scorning the sin of others both end at the same destination.
One might say that Tertullian is the Barry Bonds of the church fathers. His theological talent and ability is recognized by all, but is forever marked by an asterisk. Because he was too good for the church, Tertullian was not a great theologian.
 Pope Benedict XVI, The Fathers of the Church (Grand Rapids: William B. Eerdmans Publishing Co., 2009), 34-35.