So it was in New Testament times. If a person was not baptized, you could probably assume that he or she was not a believer. On this we must be clear: baptism is a symbol of salvation and only a symbol. But, like a wedding ring, it is such an effective symbol that it should never be taken for granted. ── Michael P. Green《Illustrations for Biblical Preaching》
Over the centuries Christians have debated what baptism accomplishes, to whom it should be administered, and how much water should be used.
Christian Theology in Plain Language, p. 158.
The story is told about the baptism of King Aengus by St. Patrick in the middle of the fifth century. Sometime during the rite, St. Patrick leaned on his sharp-pointed staff and inadvertently stabbed the king's foot. After the baptism was over, St. Patrick looked down at all the blood, realized what he had done, and begged the king's forgiveness. Why did you suffer this pain in silence, the Saint wanted to know. The king replied, "I thought it was part of the ritual."
As I shut the door of the office after me, it seemed as if I met the Lord Jesus Christ face to face. It seemed to me that I saw Him as I would see any other man. He said nothing, but looked at me in such a manner as to break me right down at His feet. I fell down at His feet, wept aloud like a child, and made such confessions as I could with my choked utterance. It seemed to me that I bathed His feet in tears. I must have continued in this state for a good while. I returned to the front office, but as I turned and was about to take a seat by the fire, I received a mighty baptism of the Holy Ghost. Without any recollection that I had ever heard the subject mentioned by any person in the world, the Holy Spirit descended upon me in a manner that seemed to come in waves of liquid love; it seemed like the very breath of God. I wept aloud with joy and love.