I would suggest that true "Biblical Christianity" is intellectually challenging if it is done correctly. I think a lot of pastors, and I would include priests, don't prepare, don't study, or take their call seriously. They just mail it in.
I recall one church I briefly attended. The sermon was 15 minutes and the whole service was over in 30 minutes. That was shallow.
Personally, I think if a Christian is not being intellectually challenged, then it is incumbent upon the Christian to do something about that.
It may require a change in churches.
It may require you to have to study on your own. This is something many don't want to do. They want to be spoon fed and not "dig" out those golden nuggets that are in the Word of God.
Personally, I'm working on a Graduate Certificate in Biblical Languages to help me better understand the New Testament. Why? I want to know more so I can be a better Christian and teacher of the Word.
Peter noted:
1Therefore, putting aside all malice and all deceit and hypocrisy and envy and all slander, 2like newborn babies, long for the pure milk of the word, so that by it you may grow in respect to salvation, 3if you have tasted the kindness of the Lord (1 Peter 2:1-3 NASB).
Well yeah, cause true "Biblical Christianity" is Catholicism. Sorry, I couldn't help myself.
There's a line from what I think is Eucharistic Prayer III from the new rite of Mass that goes something like "Father, you are holy indeed, and all creation rightly gives you praise. All life, all holiness comes from you through your Son, Jesus Christ our Lord, by the working of the Holy Spirit. From age to age you gather a people to yourself, so that from east to west a perfect offering may be made to the glory of your name."
Now, officially, because it's the new rite of Mass I can't stand it, but even after 18 years a Catholic I still wake up sometimes with those words on my lips. Those lines thrill my intellect like nothing else. I don't need a 45 minute sermon on them or even a sermon series on them. I just need to hear them and my mind goes off on flights fantastic.
Now I admit that's not a passage from Sacred Scripture so people are probably going spastic even as they read but there's something about the words that talk about the Word in Catholicism that I've not found in any other religion.