I mentioned that the problem of suffering is the starting point. There are countless answers that address this problem, or how to be "happy". We live life and try several different ideas throughout to address this problem, but the issue continues to pop up. At some point, we may decide to stop putting band aids on the problem and to try to solve it. I consider this to be the first objective of religion.
We step back and survey the landscape, not just for an easy answer, but for the solution. There are so many resources for answers in some capacity: religion/spirituality, philosophy, medicine, psychology, self-help, peer advice, etc. When there are so many answers that means there is no clear solution. This calls for the problem to be solved individually.
Now, some would say their particular religion has solved the problem but the payoff isn't until another time in the afterlife. This isn't good enough. We have to decide that the problem can be solved in the here and now.
These are the three conditions that get us to the starting point: we have to decide the problem of suffering can be solved, we have to decide that the solution is available in the here and now, and we have to rely completely on ourselves to solve it. When we commit to those three conditions, we are undertaking a huge burden, which is why it's called the narrow path.
Here is how it played out for me. I would struggle for a solution and then come up with something that I fully believed was the solution, only to eventually have it fail. Then, I would repeat this again and again. This is where faith really comes in. I have this problem that I've decided can be solved and is within my reach somehow, but I'm unable to figure it out. Further, I have to reject all solutions I come up with since I can't be trusted.
This is when we have to change our focus from solving the original problem of suffering to solving the problem that is preventing us from being able to solve the original problem. There is some underlying issue that is distorting our perception. This leads to the painstaking journey of introspection I've been talking about.
This process is the most difficult thing anyone will ever try to do. Logic and reason will never get us there. In fact, it resists the entire way. The entire thing is fueled by faith. Faith allows us to decide the problem of suffering can be solved in the here and now, and faith allows us to persist even against what the intellect says is sane, rational, and logical.
It is a lack of faith when someone doesn't accept the three conditions I've mentioned and it is a lack of faith when someone doesn't persist beyond perceived failure.