BAPTISM
Some say it is an ordinance, some say it is a commandment.
Some say it regenerates, some say it does not
I think it would be much more accurate to observe that what all Protestants greatly have in common is a denial of the Catholic distinctives (Mary, papacy, communion of saints, an infallible Church, etc.). But even then it’s not unanimous. Lutherans and Anglicans pray for the dead (C. S. Lewis believed in purgatory, and Wesley believed in some sort of intermediate state). Anglo-Catholics agree with us on several matters. Lutherans believe in the Real Presence, in a way not too far from our view).
That said, there is profound commonality, in the joint rejection of distinctively Catholic doctrines.
Acts 22:16
Romans 6:3-4 (cf. Romans 8:11, 1 Cor 15:20-23, Col 2:11-13)
1 Corinthians 6:11
Mark 16:16
Titus 3:5
John 3:5
Protestants can’t even figure out whether it regenerates or not. Some say it does; others deny it. Martin Luther certainly agreed baptism is central doctrine: right in the center of soteriology:
But when it comes to your own internal disagreements, that is something else altogether. Baptism is the classic example of non-unity in important matters (not just the so-called “secondary” ones), which is why I have always highlighted it as
an example of a disproof of the Protestant authority principle and of perspicuity of Scripture in (miserable) application.
All the major Lutheran denominations hold to baptismal regeneration. According to Mead’s Handbook of Denominations (I have a 1970 ed.), Lutherans accept Luther’s Small Catechism and Large Catechism, both of which clearly teach baptismal regeneration. The Smalcald Articles were also written by Luther. The Formula of Concord, also accepted by most if not all Lutheran bodies, states in its Article XII, section on “Erroneous Articles of the Schwenkfelders”:..
“We reject and condemn these errors . . .: 3. That the water of Baptism is not a means whereby the Lord God seals the adoption of sons and works regeneration.
Of course, to get out of this dilemma, you can always argue that Lutherans are not Protestants, or that Luther wasn’t the founder of Protestantism.
This discussion continues at
https://www.patheos.com/blogs/davearmstrong/2017/01/dialogue-protestant-unity-central-doctrines-baptism-test-case-vs-jerry-walls.html?
Further reading:
Infant Baptism: A Fictional Dialogue