Answer
Yeshua continued: Again I say unto you, that if two of you shall agree on earth as touching anything that they shall ask, it shall be done for them of my Father who is in heaven (Mt. 18:19). This verse, has been taken out of context, and many use it as a prayer promise, that if two believers agree on anything on earth, it will definitely be done, and the prayer will definitely be answered in the affirmative. This misconception has led to many disappointments. The context is not prayer, but church discipline. The two people who agree are the witnesses who confront the brother with his sin and who witness to the local church that the sinning brother had not responded appropriately (Mt. 18:15-17). Therefore, the actions of the church are based upon the testimony of the two witnesses. In turn, the decision of the church is recognized by heaven, and heaven allows Satan to take that believer’s life.
Excerpt from Yeshua - Life of Messiah Abridged version by Dr Arnold Fruchtenbaum, Ariel Ministries pg 340