God gave us brains and expects us to use them. I don't think God asks for completely blind faith. God has put knowledge of himself in our hearts. He has given us consciences and the Holy Spirit to help reveal truth to us.
It is this innate knowledge and experience that brings us to recognize the truth of scripture.
Scripture is also authenticated through the demonstration of God's foreknowledge (prophecy) and God's power (miracles). Scripture records that all of Creation speaks to God's power.
So it is both with the Mind and heart and the realization of what has been revealed to us, that we come to recognize God and God's scripture.
Once we realize that scripture is from God, then of course we would be fools to let our own experience lead us to pick and choose what parts of God's revelation we want to believe.
But we are in fact required to use our brains and hearts to make the determination in the first place. And it's useful to examine the false religions.
Both Islam and Mormonism include large elements of truth from the original scripture. But then they go on to cast doubt on the original scripture so they can introduce their own doctrines that are foriegn and contradictory to those scriptures.
Again this requires using your brain to distinguish what's the real scripture from what's the fake. What came first and what's the distortion? What was authenticated with miracles and prophecies and what was not?
Clarification: When i say it’s useful to examine the false religions, I mean, it’s best to become very very familiar with the original scripture. And then examine the false religions. By knowing the original well, you can spot the falsehoods.