Real spiritual growth necessitates a willingness to continue together in intimate, spiritual fellowship with other believers over an extended period of time, a truth Jesus modeled for us through His relationships with His apostles.
This type of fellowship requires a certain like-mindedness and agreement of conscience that is based upon a common understanding of Who God is and how He has called us to relate within our assemblies.
Of course, our first responsibility for agreement is to God, not man, a fact vividly illustrated in Amos 3 when the Lord speaks to Israel concerning their willful sin:
Hear this word that the LORD hath spoken against you, O children of Israel, against the whole family which I brought up from the land of Egypt, saying, You only have I known of all the families of the earth: therefore I will punish you for all your iniquities. Can two walk together, except they be agreed?
Every believer is charged by the Spirit to act according to conscience and walk in the light they have received:
For example, we cannot believe that denominating the body of Christ is evil–and then justify continued fellowship in a denominational setting on the basis that we don’t want to separate from these brethren just because they have not yet received light in this area.
For example, we cannot believe a papal hierarchy is an abomination but continue to fellowship in Catholic churches because of our great love for Catholic brethren.
We can never place loving the brethren above obeying God.
Walking in truth is never contrary to walking in love [the two are perfectly compatible]–and no believer should allow another believer to condemn him for following his conscience–for this is how God has ordained His light to spread.
Certainly, if everyone who knew better would quit supporting the practice of denominating the body of Christ, there would be a great enough witness to free many of the people who remained in bondage from these lies.
Unfortunately, when those who know better, continue in one accord with those who do not, there is no witness to this effect: and the unfortunate consequence is that lies gain supremacy over the truth; and many of those who knew the truth at one time, return to deception.
There are consequences for not continuing in what God has revealed:
And if ye will not be reformed by me by these things, but will walk contrary unto me; Then will I also walk contrary unto you, and will punish you yet seven times for your sins.