Mateus 18:15-20 - Bíblia Online

"And if your brother sins against you, go and show him his fault between you and him alone. If he hears you, you have won your brother. 
But if he does not hear, take along with you one or two more, so that 'by the mouth of two or three witnesses every word may be established.' 
But if he refuses to hear them, tell it to the assembly. But if he refuses even to hear the assembly, let him be to you as a heathen and a tax collector. 
Assuredly I say to you, whatever you bind on earth shall have been bound in heaven, and whatever you loose on earth shall have been loosed in heaven. 
Again, assuredly I say to you that if two of you agree on earth about anything that they may ask, it will be done for them by My Father in heaven. 
For where two or three are gathered together in My name, I am there in their midst." 

Mateus 19

"And if your brother sins against you, go and show him his fault between you and him alone. If he hears you, you have won your brother. 
But if he does not hear, take along with you one or two more, so that 'by the mouth of two or three witnesses every word may be established.' 
But if he refuses to hear them, tell it to the assembly. But if he refuses even to hear the assembly, let him be to you as a heathen and a tax collector. 
Assuredly I say to you, whatever you bind on earth shall have been bound in heaven, and whatever you loose on earth shall have been loosed in heaven. 
Again, assuredly I say to you that if two of you agree on earth about anything that they may ask, it will be done for them by My Father in heaven. 
For where two or three are gathered together in My name, I am there in their midst." 

Mateus 19