Street preaching is not the only way of evangelism but it is a good way to reach a lot of people in a short period of time. It is a Biblical way to preach, in the open air.
“Cry aloud, spare not, lift up thy voice like a trumpet, and shew my people their transgression, and the house of Jacob their sins” Isaiah 58:1
Not every way of street preaching has to be the exact same. Some Christians have different methods in doing it and that is okay. As long as correct doctrine is being preached and not a false Jesus or a cult false religion then it should not matter how others are preaching. In fact we should be happy that those who aren’t against us are for us:
“49 And John answered and said, Master, we saw one casting out devils in thy name; and we forbad him, because he followeth not with us.” 50 And Jesus said unto him, Forbid him not: for he that is not against us is for us.” Luke 9:49-50
Unfortunately some Christians want everyone to do it their way and follow their convictions. They may declare certain words are not allowed to be used or certain levels of harshness are too much. Everyone that street preaches needs to be lead by the Holy Ghost and not worry about what others think. Those who think they have a right to make the street preaching rules for everyone are putting themselves in a dangerous position.
“My brethren, be not many masters, knowing that we shall receive the greater condemnation.” James 3:1
There is no problem with going out in a very loving way and there is nothing wrong with going out in a harsh rebuking way. One on ones or full out preaching on a bullhorn. Different methods for different situations. You would preach differently at a family event than in front of a strip club. The best thing is to be able to switch gears and know what is going on around you to get the message out the best way possible of repenting of sin and turning to Jesus.
“20 And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law; 21 To them that are without law, as without law, (being not without law to God, but under the law to Christ,) that I might gain them that are without law. 22 To the weak became I as weak, that I might gain the weak: I am made all things to all men, that I might by all means save some. 23 And this I do for the gospel’s sake, that I might be partaker thereof with you.” 1 Corinthians 9:20-23
Street preaching is so effective and could reach thousands of people in one outing that the devil will do anything to stop it. Normally there is a resident demon possessed heckler that it seems Satan assigns to the preach, all they really do is scream and make weird noises. Other than that one of the best tools of the devil are the police officers. You can have someone standing and listening to the preaching and you feel you are getting somewhere with them and then the flashing lights appear, the cop walks up and the preaching stops while they question you and the listener leaves.
“And these are they by the way side, where the word is sown; but when they have heard, Satan cometh immediately, and taketh away the word that was sown in their hearts.” Mark 4:15
Most police officers are not Christians, some are but the majority probably are not. God will use them to protect preachers but they are also used by the devil to stop the message and some of them enjoy shutting down a preach, especially the ones that are into the sins or cults that you are preaching against. A Catholic police officer will always be excited to help his church and shut down or cite a street preacher trying to preach in front of a wicked Catholic Church and expose the darkness of it all to try and show the light of Jesus to those in its grips. Too bad they are not as vigilant in stopping the pedophile reprobate priests in their city before they get involved in child prostitution and physically harming kids like we have seen recently. It is ironic when the priest who calls the police on the street preachers should actually be in prison.
“But whoso shall offend one of these little ones which believe in me, it were better for him that a millstone were hanged about his neck, and [that] he were drowned in the depth of the sea.” Matthew 18:6
When we as Christians street preach we are never out there preaching for the lost people headed to Hell. We are out there solely for God and taking a stand for Him. If God uses our work for Him to reach people then to Him be the glory.