"You base your answer on the Bible, but that is what I want to know: how do you know that what's in the Bible is the truth? For instance; you say that God cannot lie because it's in the Bible. But the Bible is God's Word, so God cannot lie because God Himself says He cannot lie.
But how do you know that in itself isn't a lie? Is God obliged to tell you the truth? After all, you're his creation and He can do with you as He pleases, right?" -- Taxandrian
Tax, I do not expect you to accept that our presuppositions regarding God and Scripture are true, that would be going against Scripture's teaching itself (1 Cor. 2.14). Instead, we consistently maintain that the things we are saying about God and Scripture are true despite what others choose to believe. We have argued from the impossibility of the contrary, it is not possible that God has not revealed Himself in Scripture. So for us, there could be no greater proof than that, the impossibility of the contrary. We argue that without presupposing Christian theistic knowledge (Biblical epistemology) your question, and truth itself would be unintelligible having no rational basis for meaningful predication concerning human experience at all.
We simply argue that the God of Scripture alone can provide the necessary preconditions of rational discourse and thus predication on reality itself, anything else would be self refuting and untenable philosophically speaking. God and His revelation are the necessary preconditions to all things logical, moral, and philosophical. This is called an infinite reference point. Anything less ends in infinite regress. God, like the laws of logic, must be presupposed to be denied, thus, attempting to deny Him is actually proving His exists as the basis of the denial in the first place.
So too if you attempt to deny the laws of logic you must operate within them to make such an illogical assertion to begin with, again you end in an infinite regress. God alone provides the necessary preconditions for rational logical discourse at all, God is the reason why your questions and objections (though untenable and untrue) can make sense in the first place. Logic works because they reflect the logical thinking of God Himself, in essence, God gives logic their law-like character. If you say there are no ultimate governing laws of logic which are universal abstract and invariant (i.e. fixed) than you are asserting the irrational nature of your own discourse and thus we can all go home. This may help,
18 For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men who suppress the truth in unrighteousness, 19 because that which is known about God is evident within them; for God made it evident to them. 20 For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse. 21 For even though they knew God, they did not honor Him as God or give thanks, but they became futile in their speculations, and their foolish heart was darkened. 22 Professing to be wise, they became fools, 23 and exchanged the glory of the incorruptible God for an image in the form of corruptible man and of birds and four-footed animals and crawling creatures.
Please repent and trust in Christ in whom are hidden all the treasures of wisdom and knowledge.