“And he commandeth all men that they must repent and be baptized in his name, having perfect faith in the Holy one of Israel, or they cannot be saved in the kingdom of God.” (2 Nephi 9:15-23)
See I marvel. I marvel that the Jews who were not so blessed as to be able to suffer the wars of the Nephites and Lamanites in the Promised land, but have to stay behind in Israel and suffer the Babylonian captivity, only to return to Jerusalem, and Israel, so that the savior of the nations might be born and die for all humanity, that Abraham would be a blessing to all nations, are not given such clear prophecy concerning baptism.
Perhaps that is because if you told a Jew at the time that 2 Nephi is supposedly happening in North America, that they had to be baptized, they would not have had the foggiest clue what you were talking about. The word baptism came into Jewish parlance through Hellenistic influence. And though by the time Christ comes along in the first century, there had developed a tradition of ritualistic washing, these were not commanded in the O.T. The Pharisee’s looked on John the Baptist with suspicion for his baptism, and not without good reason. “(Now they had been sent from the Pharisees.)  They asked him, ‘Then why are you baptizing, if you are neither the Christ, nor Elijah, nor the Prophet?’" John 1:24-25 (ESV)
Infact the word baptize does not show up in the O.T. though baptism is foreshadowed in the O.T. and is also the topic of a few prophesies, but never mentioned by the name baptism. Baptism is part of the New Testament vocabulary, not that of the Old Testament. In the Old Testament people are not baptized but circumcised, and this does not change at all until the coming of Christ. The Old Testament has to be fulfilled before it can be replaced by the New Testament and the sacraments that accompany it.
“See to it that no one takes you captive by philosophy and empty deceit, according to human tradition, according to the elemental spirits of the world, and not according to Christ.  For in him the whole fullness of deity dwells bodily,  and you have been filled in him, who is the head of all rule and authority.  In him also you were circumcised with a circumcision made without hands, by putting off the body of the flesh, by the circumcision of Christ,  having been buried with him in baptism, in which you were also raised with him through faith in the powerful working of God, who raised him from the dead.  And you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him, having forgiven us all our trespasses,  by canceling the record of debt that stood against us with its legal demands. This he set aside, nailing it to the cross.  He disarmed the rulers and authorities and put them to open shame, by triumphing over them in him.”
So because there was no word for Baptism in Hebrew it could only be hinted at in the Old Testament prophecies. Instead of calling it Baptism Ezekiel describes it and says what it will do without naming it: “I will sprinkle clean water on you, and you shall be clean from all your uncleannesses, and from all your idols I will cleanse you. “ Ezekiel 36:25 (ESV) So the question really becomes, exactly what language are these people using? What language is it that Joseph Smith is translating? That they would have a word for something that has not yet been introduced? How is it that these “Hebrews” in North America have been Hellenized and their brothers who live three doors down from the Greeks in Israel have yet to be Hellenized? It is peculiar that where as the Jews left behind have to wait for Christ to come in the flesh, be crucified, die, be buried and rise again before they can be baptized into Christ’s death and resurrection, and yet those in North America are given baptism centuries before Christ. It doesn’t make sense. Not at all. For Christian baptism buries us with Christ into death, and raises us up again with Him. “We were buried therefore with him by baptism into death, in order that, just as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.” (Romans 6:4 (ESV) But how is this possible if Christ has not yet died, been buried, or come back from the dead?