Say somebody was dying and you knew that he was not baptized. Could you do it without consent? In St. Faustina’s diary I read she did this to a Jewish man who was dying.
Without the relevant quote from St. Faustina’s diary, I cannot comment upon what she did or did not do. All that I can say is that you cannot baptize against his will an adult who you have reason to know would object to being baptized. If there is reason to believe that he might have wanted baptism, you can baptize him in that case. Only an unbaptized, dying child below the age of reason can be baptized without parental consent. The reason for the difference is because some indication of faith, however small, is necessary for an adult baptism to be valid.
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