alanv: "What I was wondering is what made him start baptising people."
That is the best question anyone could ask. And no one every does. They just accept the ritual without question because "Jesus said so" and "the church says so".
I have never seen a solid, logical answer as to why John used this ritual nor what inspired him to come up with the idea. But I can guarantee you it must be something very simple and fitting to his times. I can tell you what I think it's all about.
The masses were superstitious people, no different than many people today. They were brow beaten and guilted into giving most of their income for sin debts and to "give more" to please God when they needed to ask for divine favors. Maybe even giving free labor to the church. The church beat them psychologically and sucked them dry for whatever they could take from them. The church has always been a business.
I imagine that John, and later Jesus, persuaded the people to believe that they did not have to accept the guilt and punishment from the church. All one had to do for forgiveness was "go to their brother" with an apology or restitution. They could take matters up directly with "God" and so Jesus taught them how to pray so that they would not need the holier than thou Pharisees as their intercessor. And to seal the deal that they were remorseful for past deeds and would try to live a better life, the baptism was an outward show of "becoming clean". It appealed to their superstitious nature of needing to have some type of ritual of confirmation that they had been forgiven. I think that is the key to it. Wiping the slate clean, leaving behind the baggage, and making a fresh start in life. It also gave them independence from the heavy yoke of church doctrines and rituals. They no longer needed the church.
There were also secret society groups even before Jesus's time. And during Jesus's lifetime, I find evidence that leads me to believe the secret societies had infiltrated the Sanhedrin. Sometimes the common people are recruited into a lower rank of these secret groups because the elite need spies and footsoldiers where they cannot go. For those members, it was especially dangerous to make an outward show that they were breaking their bonds of an oath sworn on their own life. But it was an opportunity for them to free themselves from the darkside. Superstition played a part even with them as they believed the act of baptism would bring them under the protection of a God more powerful than the brotherhood.
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In my opinion, organizations like WT have turned baptism into a legalistic manuever, which is not what it was ever intended to be.
Religions have changed what was intended to be an expression of freedom from the bondages of religion, to an incorporation of legalism. It is only through the act of baptism, that you now become a church member or a WT slave. It is because of baptism that the state and courts cannot help you out of any matters dealing with abuse from religion. The baptism of today has become a visual oath, a seal of contract, that you now, willingly, give your religion and it's declarations, authority over your life. This is why you are expected to write a DA letter to "break your contract". And guess what? Without written acknowledgement and acceptance of your DA by the other party, you are still considered under contract! It must be reciprocal to be legally broken.
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Here is some idiocy put out by religions as to the meaning of baptism:
"Baptism is a burial in water to symbolize Christ's burial." (Odd explanation considering someone else started it before Christ even knew about it and there is no scriptural basis for this statement.)
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According to Online Etymology Dictionary:
Baptism
c.1300, bapteme , from O.Fr. batesme, bapteme (11c., Mod.Fr. baptême ), from L. baptismus , from Gk. baptismos , noun of action from baptizein (see baptize). The -s- restored in later 14c. Figurative sense is from late 14c. Phrase baptism of fire "a soldier's first experience of battle" (1857) translates Fr. baptême de feu ; the phrase originally was ecclesiastical Gk. baptisma pyros and meant "the grace of the Holy Spirit as imparted through baptism." Later it was used of martyrdom, especially by burning. Baptize
c.1300, from O.Fr. batisier (11c.), from L. baptizare, from Gk. baptizein "to immerse, to dip in water," also used figuratively, e.g. "to be over one's head" (in debt, etc.), "to be soaked (in wine);" in Gk. Christian usage, "baptize;" from baptein "to dip, steep, dye, color," from PIE base *gwabh- "to dip, sink." Christian baptism originally consisted in full immersion. Related: Baptismal (adj., 1640s). -----------
In thinking about the etymology of the the word, "Baphomet" comes to mind, probably because of the similarilty of the word and its uniqueness.
The name Baphomet first appears around 1195 .. ...
The name Baphomet comes up in several of these confessions, in reference to an idol of some type that the Templars were alleged to have worshipped. The description of the object changed from confession to confession. Some Templars denied any knowledge of it. Others, under torture, described it as being either a severed head, a cat, or a head with three faces. [ 4 ]