Oddly enough I received several questions concerning Tertullian within about an hour. You may read him here. I have listed some quotes from him below which may be of interest.
We Christians are forbidden to introduce anything on our own authority or to choose what someone else introduces on his own authority. Our authorities are the Lord’s apostles, and they in turn chose to introduce nothing on their own authority. They faithfully passed on to the nations the teaching which they had received from Christ. So we should anathematize even an angel from heaven if he were to preach a different gospel. (Tertullian 487)
These are human and demonic doctrines, engendered for itching ears by the ingenuity of that worldly wisdom which the Lord called foolishness, choosing the foolish things of the world to put philosophy to shame. For worldly wisdom culminates in philosophy with its rash interpretation of God’s nature and purpose. It is philosophy that supplies the heresies with their equipment. (Tertullian 488)
What has Jerusalem to do with Athens, the Church with the Academy, the Christian with the heretic? Our principles come from the Porch of Solomon, who had himself taught that the Lord is to be sought in simplicity of heart. I have no use for a Stoic or a Platonic or a dialectic Christianity. After Jesus Christ we have no need of speculation, after the Gospel no need of research. When we come to believe, we have no desire to believe anything else; for we begin by believing that there is nothing else which we have to believe. (Tertullian 488)
My first principle is this. Christ laid down one definite system of truth which the world must believe without qualification, and which we must seek precisely in order to believe it when we find it. Now you cannot search indefinitely for a single definite truth. You must seek until you find, and when you find, you must believe. Then you have simply to keep what you have come to believe, since you also believe that there is nothing else to believe, and therefore nothing else to seek, once you have found and believed what he taught who bids you seek nothing beyond what he taught. If you feel any doubt as to what this truth is, I undertake to establish that Christ’s teaching is to be found with us. For the moment, my confidence in my proof allow me to anticipate it, and I warn certain people not to seek for anything beyond what they came to believe, for that was all they needed to seek for. They must not interpret, ‘Seek, and ye shall find,’ without regard to reasonable methods of exegesis. (Tertullian 489)
What you must seek is what Christ taught, and precisely as long as you are not finding it, precisely until you do find it. And you did find it when you came to believe. You would not have believed if you had not found, just as you would not have sought except in order to find. Since finding was the object of your search and belief of your finding, your acceptance of the faith debars any prolongation of seeking and finding. The very success of your seeking has set up this limitation for you. Your boundary has been marked out by him who would not have you believe, and so would not have you seek, outside the limits of his teaching. (Tertullian 489)
But if we are bound to go on seeking as long as there is any possibility of finding, simply because so much has been taught by others as well, we shall be always seeking and never believing. What end will there be to seeking? What point of rest for belief? Where the fruition of finding? With Marcion? But Valentinus also propounds: ‘Seek, and ye shall find.’ With Valentinus? But Apelles also will knock at my door with the same pronouncement, and Ebion and Simon and the whole row of them can find no other way to ingratiate themselves with me and bring me over to their side. There will be no end, as long as I meet everywhere with, ‘Seek and ye shall find,’ and I shall wish I had never begun to seek, if I never grasp what Christ taught, what should be sought, what must be believed. (Tertullian 489)
Linda Zagzebski and Timothy D. Miller. Readings in Philosophy of Religion Ancient to Contemporary. Blackwell Publishing Ltd. UK. 2009. Pgs. 487-489.