Cruft asks: "Is baptism a work required without which we are NOT saved?"
I've thought about answering this several different ways. Instead of doing that, I'm going to talk about myself and the subject. Mostly because I don't particularly enjoy internet arguments. I was raised in a legalistic church environment, then my folks sent me to a baptist school in jr high. I eventually graduated from a christian college (protestant) and obtained another degree from another college (catholic, benedictine). I used to really get off on arguing the finer points of doctrine with others both my own age and my instructors. I've even done that on the internet. Now that I'm older, and hopefully wiser, I realize that arguing on the internet is a waste of time and energy.
My post before this one was an attempt to gain some understanding about the Jewish practice of mikveh and how that relates to christian baptism, not to engage the topic of how Christians see baptism today. My understanding of Christianity is far from perfect. I am very much aware of how different denominational schools of thought have developed over the years, most of which have come about as a reaction against some other school of thought. I'm not interested in being a Coptic, Syriac, Orthodox, Catholic, Protestant, Anabaptist, Calvinist, Armenian, Messianic or any other denomination or division or whatever your particular special branch and belief system is called. I am interested in being as much like Jesus as I can and learning about how He wants me to see things and practice His religion. Thats why I'm taking another look at the topic of baptism, this time from the point of view, at least as close as I can get to the point of view, of a 1st century Jewish Christian.
What I've learned so far is that "baptism" as I've understood it, is probably not the same rite as what the hearers of Peters sermon in Acts chapter 2 understood it to be. Despite what the catholic church teaches, they are not doing the same thing that Peter did and taught. I think its reasonable to disregard the opinions of BOTH the RCC and those that have based their doctrine on a reaction to the RCC. What I want to know is what did "baptism" mean to these people? Its only recently that I learned that Jews had a word and a practice for the Greek word "baptisim". That word is "mikveh".
I can't prove it, (the NT is written in Greek) but I suspect the word Peter actual said in Acts 2 was "mikveh". I'm becoming convinced that "mikveh" was what John the Baptist was doing and that it was what Jesus was teaching and his disciples were doing as well. "Mikveh" had a whole connotation to them that "baptism" doesn't seem to have to us today.
Jesus (and the 12) taught people to do what we call "baptism". To them baptism was neither a work that required God to grant salvation (sacrament), nor a mere outward sign of an inward belief (outdated, inconvenient, and totally optional non requirement). It was rather an appeal to God for forgiveness. The complete Jewish Bible words 1 Peter 3:21 this way, "This also prefigures what delivers us now, the water of immersion, which is not the removal of dirt from the body, but one’s pledge to keep a good conscience toward God, through the resurrection of Yeshua the Messiah.".
My current understanding of the topic is this:
Baptism is not a work as expressed typically in the Catholic/Protestant sacramental debate.
Nor is Baptism a non issue as understood from the Calvinist irresistible grace tradition.
Baptism meant something more to Jesus, the 12 and those who responded by doing it than what we think of today. It meant something closer to "mikveh" and they "mikevhed" without ever considering any of the points we get hung up on. They did it to be "right with God", to "be clean" to be able to worship and draw close to the creator, not to be able to divide believers into camps along purely academic and nonsensical lines.
Mark 16:16 quotes Jesus as saying: "He who believes and is baptized will be saved; but he who does not believe will be condemned."
Cruft, my short answer is, "what Jesus said, taught and did".