Paul is speaking here of being unified in the faith Ephesians 4:1-15
I have just been reading the letters in the New Testament which Peter and John sent to the early church members, or saints. It must have been a saddening experience for them to see other men vying to take over the leadership of the congregations of saints. These men had decided that they knew more, and were better able to direct the church, than the apostles whom the Savior had called to lead His people. The apostles Peter and John had been with the Savior in His ministry. Even after His death and resurrection, they regularly received revelation from Him on how He wanted His church to be lead. (see Peter receiving revelation to take the teachings of Christ to the gentiles; Acts 10:1-48 and 11:1-18) These were great men who could personally testify of the divine mission of the Savior.
As the early church began to grow, there appeared men who John called "antichrists". I can see why he called them "antichrists", since their goal was to as get people to follow them instead of Christ. These prideful men wanted power. They wanted to control people. To do this they made up appealing "beliefs", and then tried to get the early saints to follow them instead of their leaders who followed the Savior's direction.
