Is Baptism in water a work or a command? Is it necessary for salvation?

I understand your reasoning and very much have appreciated your replies.
The reason I disagree with you is because of what Ephesians 2:8-9 teaches. We are saved by grace through faith...thus, faith is sufficient for salvation. As if to reinforce this point, Paul goes on to add...not of works. He anticipated, particularly from Jews, that they would believe something more than faith would be necessary. And, he finishes by telling them that though works don't produce salvation, God has ordained works for us to walk in.

I agree with Eph. 2:8-9. Our understanding of those verses have to be in agreement with the rest of the scriptures.
Faith is sufficient but what does it mean to have faith that is sufficient.
22 You see that faith was working with his works, and as a result of the works, faith was perfected; 23 and the Scripture was fulfilled which says, “And Abraham believed God, and it was credited to him as righteousness,” and he was called a friend of God. 24 You see that a person is justified by works and not by faith alone.

You actually don't believe faith is sufficient if something must be yet still done. Galatians 2:16...by works of the law shall no flesh be justified.
So we have 2 verses of scripture that seem to say 2 very opposite things. How do you reconcile them?

Faith that has no works is dead. Faith that works is faith made complete.

In Galatians 2 Paul is talking about a specific set of works.
16 nevertheless, knowing that a person is not justified by works of the Law but through faith in Christ Jesus,
He's talking about the law of Moses and circumcision.

I've never seen anyone baptized in fire... have you?

No. But I know many baptized as by fire. And fire is what was upon the Apostles the day of Pentecost at the coming of the Holy Spirit.

can you add clarification to that?

Yes. On the apostles only.

Agree. Jesus connected Holy Spirit baptism with salvation. They occur at the same time. Rituals like tub-dunking and foot washing and communion come later and are done for remembrance and illustration.

Baptism is not a "work of the law" .... it is an act of obedience to God. That is not a "work".

I know that our works are tried by fire.

1 Corinthians 3:15
“If any man's work shall be burned, he shall suffer loss: but he himself shall be saved; yet so as by fire.”

And then we have this verse;

1 Peter 1:7
“That the trial of your faith, being much more precious than of gold that perisheth, though it be tried with fire, might be found unto praise and honour and glory at the appearing of Jesus Christ:”

Are you referring to water baptism or Spirit Baptism?

Water baptism is an act in the same sense that partaking in communion services and foot washing services are, but it is not salvational.

Baptism by fire is simply to learn something first hand by doing it, usually of necessity. No different from a Christian learning some aspect of the faith as a result of trial.

Yes. To authenticate the presence of the Holy Spirit upon them. This was the power Jesus had told them to wait for. God isn't prohibited from doing the same again, but Pentecost was a unique case as it marked the beginning of the church. But there are still signs and wonders that accompany the believers. And spiritual people don't require outward signs. They know when the Spirit comes in power. They can see the effect it has on others and themselves. Only unspiritual people need an outward sign.
I'm of the belief that Peter recognized this in those in Acts 2 because of their response. Clearly not everyone believes this. But Jesus dealt with a similar situation when He healed the paralytic man. Having pronounced the man's sins forgiven, He went on to heal the man to authenticate His original pronouncement.
You and I wouldn't have need of a miracle if Jesus forgave someone's sins today. We simply believe it by faith.
Peter preached to the whole crowd. But He only told those who asked how to respond. I am interested, though, what happens during water baptism that saves a person? What transpires? What is it about the water that makes a dead man alive?

What is a work of the law?

There's no indication that this is true. Are you a "baby burner"??

It helps to drop in an electric toaster or hair dryer.

Romans 1:
18For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold the truth in unrighteousness;
19Because that which may be known of God is manifest in them; for God hath shewed it unto them.
20For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse:
21Because that, when they knew God, they glorified him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.
22Professing themselves to be wise, they became fools,
23And changed the glory of the uncorruptible God into an image made like to corruptible man, and to birds, and fourfooted beasts, and creeping things.
24Wherefore God also gave them up to uncleanness through the lusts of their own hearts, to dishonour their own bodies between themselves:
25Who changed the truth of God into a lie, and worshipped and served the creature more than the Creator, who is blessed for ever. Amen.

Go to the graveyard and preach and let me know how many people respond. And God can quicken a baby. John the Baptist leapt in the womb when Jesus arrived in another womb. God isn't limited in any way in His ability to save.

Sure men can know that God exists. They can even know they are accountable to Him. But they can't give themselves life.