I know the fundamentals of salvation, and I know why they are necessary.
Imperfection exists. This is a given. In the light of eternity, however, there can be no partial good or evil. Minor flaws - that is, misuses of what is good - extended over infinite time without chance of correction logically means the misuse of everything good. Therefore, in the light of eternity, perfection or total depravity are the only options.
However, achieving perfection is impossible for humanity left to its own devices. Grace is needed - an unmerited forgiveness, a get out of jail free card. However, justice must also be satisfied. We tend to brush over that part, but really, we do some pretty terrible things. If someone doesn't pay the price, the universe would be treating good and evil acts alike. Doesn't seem fair to me.
Second problem: the price is too much for us to pay. For the hurt that we cause people, for the selfishness that allows us to buy a plasma TV when hundreds of people could be fed on what it costs us, for the brokenness of a world that sees poverty as a crime and genocide as an unfortunate fact of someone else's life, no price is too high. The price is life. And that is the price that God exacted... from himself. It was the only way to punish evil and forgive it. It was the only way to fulfill justice and promise mercy.
In the death of Jesus Christ, humanity was given a clean slate. In his resurrection, we were given the means to change our most fundamental nature: to abandon selfishness, because sacrifice means reward. To obey, because conscious obedience is the only real freedom. To die without fear, because in our end is our beginning.
When we confess with our mouths that Jesus is Lord and believe in our hearts that God raised him from the dead, that is what we mean. We are acknowledging a new reality. We are placing our trust in grace, and in a love beyond our understanding that died to offer it to us.
I don't think God cares how you say it, or whether you understand what he has done. None of us understands it perfectly. The upshot of it all is, we all need help to get to heaven, and we're all going to get it if we want it.