This is an interesting and important question. My Lutheran friends will not agree with me, but I think we can distinguish Luther’s view of baptism from a later Lutheran view of baptism.
Later confessional Lutherans say that baptism regenerates and, therefore, an infant who receives baptism receives regenerating grace in the water of baptism. Now, that creates certain pastoral problems for them because it means that regenerating grace, in some cases, is lost or at least not finally efficacious. I am not persuaded that’s what Luther actually taught, though that is debatable.
Luther certainly wanted to stress the importance of baptism, the promises that God makes in baptism, and the reliability of God’s promises in baptism. But if you read the old Dutch Reformed baptismal form, which was written in the sixteenth century, it too is very strong on the promises that God has made in baptism and the reliability of God to His promises, so much so that some Presbyterians think it teaches baptismal regeneration when they hear it read. It doesn’t teach baptismal regeneration, but it does teach that baptism comes to everyone baptized with the strong promise that God will save everyone who receives the promises of baptism in faith.
I think that’s very much what Luther said as well. When you read, for example, Luther’s Large Catechism on baptism, I don’t think there’s a word in there that we don’t agree with. We should exalt baptism as a great comfort, help, and encouragement to us as Christians.