Titus 3:4-7 (ESV)
But when the goodness and loving kindness of God our Savior appeared,  he saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit,  whom he poured out on us richly through Jesus Christ our Savior,  so that being justified by his grace we might become heirs according to the hope of eternal life.
This is the answer to our foolishness, we have been baptized. We have had the Holy Spirit poured out on us richly in the washing of regeneration and renewal. If I had a dime for every time I have heard that this is not talking about baptism, I would be a rich man. Problem is, I have never heard anyone tell me what this verse is talking about if it is not talking about baptism. We are saved not by our works, but by the washing of regeneration. Can someone point to another washing Jesus might be talking about here other than Baptism? Why the washing language?
Lutheran’s often don’t realize this, but the Bible is on our side, not on that of the Baptists. Baptists actually have to ignore scripture to come up with their theology. There is a reason us Lutherans are the first to proclaim sola Scriptura. It is a shame that so many Lutherans don’t know scripture well enough to argue effectively with the Baptists, and therefore are led astray by them. But that some are ignorant of the scriptural basis for our theology does not mean that we do not have a scriptural basis for our theology. We do, it is the Baptist who is on shaky ground defending his doctrine on the basis of Scripture, not the Lutheran.