As Lutheran Christians we understand baptism to be a special way in which we enter in the mystical body of Jesus Christ. Through baptism we are linked to the death and resurrection of Jesus Christ, and are claimed as God's own children.
It is a powerful time of God acting in our lives. Because baptism is about God's action not ours, any age is appropriate to be baptized. By tradition, many are baptized as infants, but there is nothing shameful in seeking baptism later in life. God welcomes all.
We also teach that one baptism is sufficient. No matter what you've done since your baptism God's actions at your baptism still apply. You are welcomed by grace into God's Church.