Suey, I feel I must speak up in answer to your original questions.

First, there are many things in the Bible that are figurative. This is seen when Christ asks the Father to make the disciples one, even as Jesus and his father are one (John 17: 11, 22). Since it is not possible for two people to literally be one, this must be figurative. However, there are other things that are not figurative, such as the need to be baptized (John 3: 5). There are two ways to know the difference, and I mean know, not simply believe, but truly know. The first, as has been mentioned, is to pray. God has promised wisdom to all who pray in true faith. The second is to listen to those whom God has chosen to act as his mouth piece on earth, the holy prophets. Simple study and discussion will never be enough.

Second, while it is true that Christ was baptized at the age of thirty, he is an exception to the rule, as he was perfect. We, on the other hand, are not perfect, and therefore require baptism at a much earlier age. I believe that in 1 Peter 3: 20-21 it states that the age of baptism is eight years (the number of people on the ark). So, we must be baptised as soon as we can, for if we delay we run the risk of not getting baptised before we die, and thus being denied the salvation God has promised.

Lastly, Christ never did go door to door in the general sense, and neither did the early apostles and disciples. The servecd missions, yes, but in a different manner. Christ never had to seek out people to teach. His ministry was only among the jews, and they flocked to him. The early apostles and disciples generally went to public places to teach. Paul frequently went into their synogogues or religious services and taught their. He and others taught in the town centers, and market places (Mars Hill being a famous occassion). On occassion they would go outside the town to places of gathering, such as where the women washed closed, or where the men worked.

So, while they did preach the gospel, it was not in the same form as it is today. However it was also a different culture, and therefore different methods were needed. In the USA if you tried to preach in a public area you would be sued under the Establishment of Religion clause. Also, very few people would listen to you, as they live a much faster passed life. You have to reach them when they are available, which is when they are home. This brings the need for door to door tracting.

I hope this answers your questions.