Really doubt you could ever really explain "true Catholic doctrine" other than being your theology opinion. So why did you think it necessary when you are unable to even answer my question ..
I can explain it as well as demonstrate its foundations. But, perhaps to encapsulate, this teaching sums it up best.
"
At the evening of life we shall be judged on our love."
You are obligated to love, in response to the love that God has shown you. That's what makes you who you were created to be, That's why you're here, to come to know and to fellowship with Him so that you may become like Him and be with Him. That's the essence of your salvation.
A friend recently told me that if you hang out with drug users you'll eventually become a user too. It's who you hang out with. And turning to God in faith is a turning away from the world and the attractions, the sin, that it offers, and jumping on board with Him instead.
And It's a challenge, a struggle, a battle, to come to increasingly value Him and so to draw nearer to Him, and away from our flesh, throughout our lives. It's not just some one-time act of faith but a continuous one where you pick up your cross daily and follow, doing His will to the best you can with the ever-present help of His grace, with all you've been given by Him. And the more you do His will, the more yet that He gives.
As far as baptism, Jesus both modeled it and commanded it, and that's how the church received it at the beginning. The church, in both the east and west, has never known any other way but to baptize as a formal means of entering God's fold as we turn to Him in faith. In fact, baptism is known as the "sacrament of faith".
Can it be done mechanically, legalistically, without faith, without the proper disposition? Yes, of course,
anything can be when humans are involved, including altar calls. As far as infants are concerned, that's another practice that goes back to the beginning with the understanding that there's a corporate aspect to salvation where we're used in each others walk. The faith of the family and community are said to stand in for the infant until they reach the age of reason and can then confirm or deny their baptismal vows for themselves. Other denominations also hold to this view.
And that brings up another point. Just as people who hold to the doctrine of sola scriptura have been disagreeing with each other on this very thread, others, based on Scripture alone, have disagreed all day long since the Reformation on issues such as baptismal regeneration and infant baptism, resulting in more splintering and schisms yet. Luther actually predicted, and worried, that such could occur once that door was opened.
Can God save without the benefit of baptism? Of course He can. But, again, the more we know, the more accountable we will be for our actions- so we do what He says, when we know it.
