FAQ:Should we stop others from preaching in the name of Jesus?

No, both Jesus Christ and Paul says that we shouldn’t stop anyone from preaching Christ.

Mark 9:38-50 KJV
[38] And John answered him, saying, Master, we saw one casting out devils in thy name, and he followeth not us: and we forbad him, because he followeth not us. 
[39] But Jesus said,  Forbid him not: for there is no man which shall do a miracle in my name, that can lightly speak evil of me. [40] For he that is not against us is on our part. 
[41] For whosoever shall give you a cup of water to drink in my name, because ye belong to Christ, verily I say unto you, he shall not lose his reward. 
[42] And whosoever shall offend one of these little ones that believe in me, it is better for him that a millstone were hanged about his neck, and he were cast into the sea. 
[43] And if thy hand offend thee, cut it off: it is better for thee to enter into life maimed, than having two hands to go into hell, into the fire that never shall be quenched: 
[44] Where their worm dieth not, and the fire is not quenched.
 [45] And if thy foot offend thee, cut it off: it is better for thee to enter halt into life, than having two feet to be cast into hell, into the fire that never shall be quenched: 
[46] Where their worm dieth not, and the fire is not quenched. 
[47] And if thine eye offend thee, pluck it out: it is better for thee to enter into the kingdom of God with one eye, than having two eyes to be cast into hell fire: 
[48] Where their worm dieth not, and the fire is not quenched. 
[49] For every one shall be salted with fire, and every sacrifice shall be salted with salt. 
[50] Salt is good: but if the salt have lost his saltness, wherewith will ye season it? Have salt in yourselves, and have peace one with another.

Philippians 1:15-21 KJV
[15] Some indeed preach Christ even of envy and strife; and some also of good will: 
[16] The one preach Christ of contention, not sincerely, supposing to add affliction to my bonds:
 [17] But the other of love, knowing that I am set for the defence of the gospel. [18] What then? notwithstanding, every way, whether in pretence, or in truth, Christ is preached; and I therein do rejoice, yea, and will rejoice. 
[19] For I know that this shall turn to my salvation through your prayer, and the supply of the Spirit of Jesus Christ, 
[20] According to my earnest expectation and my hope, that in nothing I shall be ashamed, but that with all boldness, as always, so now also Christ shall be magnified in my body, whether it be by life, or by death. 
[21] For to me to live is Christ, and to die is gain.

Instead depart or remain quiet.

Titus 3:9-11 KJV
[9] But avoid foolish questions, and genealogies, and contentions, and strivings about the law; for they are unprofitable and vain. 
[10] A man that is an heretick after the first and second admonition reject; 
[11] Knowing that he that is such is subverted, and sinneth, being condemned of himself.

Debate is a sin.

Romans 1:29-32 KJV
[29] Being filled with all unrighteousness, fornication, wickedness, covetousness, maliciousness; full of envy, murder, debate, deceit, malignity; whisperers, 
[30] Backbiters, haters of God, despiteful, proud, boasters, inventors of evil things, disobedient to parents, 
[31] Without understanding, covenantbreakers, without natural affection, implacable, unmerciful: 
[32]  Who knowing the judgment of God, that they which commit such things are worthy of death , not only do the same, but have pleasure in them that do them.