Principle 16 A person is baptized once. Because of the unfailing nature of God’s promise, and because of God’s once-for-all action in Christ. Baptism is not repeated.
Application 16B ‘Re-baptism’ is to be avoided since it causes doubt, focusing attention on the always-failing adequacy of our action or our faith. Baptized persons who come to new depth of conviction in faith are invited to an Affirmation of Baptism in the life of the congregation.
The Church of Jesus Christ of Latter Day Saints poses an interesting test case for us. In Luther’s day, questions concerning the validity of Baptism usually related to the liturgical ingredients of the ceremony. Few groups claiming to be Christian but unrecognized by the church catholic were baptizing. So Luther identifies two chief parts in the sacrament: water and God’s Word:
What is Baptism? Baptism is not merely water, but it is water used according to God’s command and connected with God’s Word.
What is this Word of God? As recorded in Matthew 28:19, our Lord Jesus Christ said, "Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit." (Small Catechism)
Today, we ask more than "Was water used?" and "Were the words ‘Father, Son, and Holy Spirit’ used?" Our concern must focus on faithfulness to the Word of God. When Christians baptize, they do so trusting that God will act to join the baptized to the life of the Holy Trinity—one God, Father, Son, and Holy Spirit. This faith is found where a genuine Christian Baptism has occurred. The Church of Jesus Christ of Latter Day Saints does not hold the traditional Christian teaching about the Holy Trinity. Rather, it seems to treat each person of the Trinity as a separate deity. Because the faith of the church is different from Mormon teaching, whether or not Mormon baptism is a Christian Baptism is a valid question. "Outside the context of trinitarian life and teaching no Christian Baptism takes place, whatever liturgical formula may be used." (The Use of the Means of Grace, application 24D)
The last statement moves us beyond issues about the liturgical rite and points us to consider the teaching of the church and its faith in a trinitarian God. Although Mormons may use water — and lots of it — and while they may say "Father, Son, and Holy Spirit," their teaching about the nature of God is substantially different from that of orthodox, creedal Christianity. Because the Mormon understanding of the Word of God is not the same as the Christian understanding, it is correct to say that Christian Baptism has not taken place. A former Mormon joining an ELCA congregation may be offered Christian Baptism (not rebaptism).
This answer poses a difficult pastoral question. If a former Mormon is anxious to embrace orthodox Christian teaching and practice and is looking to make a radical break from former memberships, then the invitation to Christian Baptism is likely to be welcomed. On the other hand, former Mormons seeking to maintain continuity with Mormonism may see the suggestion that they are not baptized or have not been Christian as an attack on who they have understood themselves to be.
Finding a way to welcome former Mormons who are not ready for a complete break with their past fellowship may require a gentle and loving pastoral hand. Maintaining the integrity of God’s act in Baptism as well as careful pastoral care are both required.
I a Lutheran wants to join the Church of JESUS CHRIST of Latter Day Saints.... they are BAPTISED.. so from that do we then say that Lutherans aren’t Christians???
Look I am just making the point that each Christian demonination has its own interpretation of scripture, baptism, etc.
The worship of JESUS CHRIST as Lord and Savior ties us all together........
THe petty finger pointing calling this or that demonination non Christian is ridiculous. there was day when many Protestant denominations said Roman Catholics were not Christians some still believe that ...even though they were the first Christian Church!!!