Much to my dismay, there have been those who would consider themselves in the camp of Presuppositional/Covenantal apologetics that have moved away from the idea that we can be epistemically (having to do with knowledge) certain of our faith. Contrary to their claims, the Apostles knew nothing of an uncertain apologetic. This has been argued many times by Presuppositionalist/Covenantal apologists such as Dr. Greg Bahnsen.
I appreciated how Dr. Lane Tipton defined the distinctive of The Westminster approach to apologetics (i.e. The reformed, biblical, covenantal approach) in a Youtube video entitled “Christ-Centered Apologetics”
Where I think our distinctive rests in the fact that we begin self-consciously with the recognition that every thought must be taken captive to Jesus Christ as Lord.
Here he brings to mind where we must start in our approach to apologetics, that is with the fact that Jesus Christ is Lord, according to the Scriptures. The Scripture he quotes is from 2 Corinthians 10:5;
We are destroying speculations and every lofty thing raised up against the knowledge of God, and we are taking every thought captive to the obedience of Christ, (2 Cor 10:5) NAS
That being said, We move on to the focus of our discussion. Dr. Tipton goes on to address Paul’s teaching in Colossians 2,
Paul for instance, in Colossians 2:8, reminds us that there are basically two approaches to philosophy, two approaches to looking at matter philosophically. There is an approach that begins, that is based on elementary principles of this world in human tradition on the one hand, and then there’s the approach that relies on Christ, and His Word. Westminster Theological Seminary seeks to begin it’s apologetic by submitting to the Christ of Scripture. And the Christ of Scripture, as Paul presents Him in Colossians, chapters one and two, is a Christ who is not only Lord as resurrected from the dead, but He is the eternal image of the invisible God, The Firstborn from among the dead, the Firstborn over all creation; and the One who has made all things, visible and invisible. He is one, Who is therefore, properly, the center. Properly, supreme. And in His resurrection, of course, He is preeminent in all things
Here we see Dr. Tipton giving us a brief explanation of why the Westminster Apologetic is so intent on a Biblical philosophy. One that is informed by their Theology, and not on man’s traditions. This is why it is always common for those of this view to ask other Christians “Where are you standing?”. If it isn’t on the self-conscious realization of Christ’s Lordship in all areas, including philosophy, then it is not consistent Christian theism. That is why we always run the self-conscious check on our brethren in the faith!
Paul, in Colossians chapter 2, tells us that it is Christ
in whom are hidden all the treasures of wisdom and knowledge (Col 2:3)
What are these treasures? Paul qualified this in verse 2 as
all the riches of full assurance of understanding and the knowledge of God’s mystery, which is Christ,
Greg Bahnsen, in his explanation of this Scripture, has this to say about Colossians 2:3-8
To put aside your Christian commitments when it comes to defending the faith is willfully to steer away from the only path to wisdom and truth found in Christ. It is not the end or outcome of knowledge to fear the Lord; it is the beginning of knowledge to reverence Him (Prov. 1:7; 9:10). Paul draws to our attention the impossibility of neutrality “in order that no one delude you with crafty speech.” Instead we must, as Paul exhorts, be steadfast, confirmed, rooted, and established in the faith as we were taught (v. 7). 
Later he says about this Scripture, as Dr. Tipton did,
That “philosophy” which does not find its starting point and direction in Christ is further described by Paul in Colossians 2:8. Paul is not against the “love of wisdom” (i.e., “philosophy” from the Greek) per se. Philosophy is fine as long as one properly finds genuine wisdom – which means, for Paul, finding it in Christ (Col. 2:3). However, there is a kind of “philosophy” which does not begin with the truth of God, the teaching of Christ. Instead this philosophy takes its direction and finds its origin in the accepted principles of the world’s intellectuals – in the traditions of men.
What then of epistemic certainty? Well, if our philosophical terms are rooted in the philosophy that is according to Christ, then we can have certainty of the truth of Scripture. Why? Because it is God’s Word, and God’s Word is true! If our philosophical terms are according to the principalities of this world, the traditions of men, then it will end up as vain deceit. Our Christian brethren in evidentialist, traditional, and putatively presuppositional circles would not like to hear this. This should not keep us from defending the faith as Paul did, proclaiming that:
“the times of ignorance God overlooked, but now he commands all people everywhere to repent, (Acts 17:30)
because he has fixed a day on which he will judge the world in righteousness by a man whom he has appointed; and of this he has given assurance to all by raising him from the dead.” (Acts 17:31)