If we were to believe in any certain religion based on faith only, then every person would have faith in a religion based on the religion they were given when they were born. That is why we were given mind and brain by God, so that we can find the truth. So that we can decide which one is the most that our mind can accept.
Truth has levels. Knowledge has levels. The mind has potential. There are going to be different levels of understanding of the "religion" by even people who follow the true one.
However, there is a reason why belief and faith is emphasized on. If God wanted to, he could've made the truth clear as daylight like he will on the day of judgment. Then no soul can deny truth and there is no room for denial at all.
But would souls love God and strive for him, if he was that open. Some would, but they are the Prophets and chosen ones and chosen close Angels. The fact this trial is made a bit difficult and that God is to large degree hidden, despite proofs around us and signs.
Fearing and hoping in God is only noble if God to some degree is unseen. Otherwise it's trivial.
However, there is also pursuit of certainty in knowledge of God, that can bring you towards day of judgment type certainty. This is noble to and because it required it to start as a seed and grow to that, and it started with faith in the unseen signs to tranquility in them to certainty, that it's noble.
Because God is hidden, seeking this certainty in knowledge is noble. If God was openly manifest as he will be on the day of judgment, then there is no room for denial, and it's a trivial type certainty.
So part of this seeking truth is to let others seek it at their pace. When someone reaches a high level and wants to bring everyone to it, he will fail. God knows how to layer the truth through his revelations, holy books, and leaders that guide by the truth.
In reality, the truth is a continuous revelation. Even Mohammad (s) was told to say "and increase me in knowledge".
