The Baha'i Writings explain:
Man cannot free himself from the rage of the carnal passions except by the help of the Holy Spirit. That is why He says baptism with the spirit, with water and with fire is necessary, and that it is essential-that is to say, the spirit of divine bounty, the water of knowledge and life, and the fire of the love of God. Man must be baptized with this spirit, this water and this fire so as to become filled with the eternal bounty. Otherwise, what is the use of baptizing with material water? No, this baptism with water was a symbol of repentance, and of seeking forgiveness of sins. (10:17)

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