Does the lack of unity and integrity in the ministry affect the people to whom we are reaching out? Is this a problem only due to egos or is there some other reason for this?
"For if the trumpet makes an uncertain sound, who will prepare himself for battle?" (I Corinthians 14:8).
In the above quote, Paul was referring to messages that are not understandable; in particular, trying to teach the gospel in a language that isn't understood by the audience. Yet, a similar problem occurs when multiple people teach different things. Hearing opposing views on the Bible can make it difficult to sort out the truth from the falsehood.
Some people want unity so badly that they are willing to overlook falsehoods just so they can say they get along with other people. The problem is that God has not given multiple messages.
"I marvel that you are turning away so soon from Him who called you in the grace of Christ, to a different gospel, which is not another; but there are some who trouble you and want to pervert the gospel of Christ. But even if we, or an angel from heaven, preach any other gospel to you than what we have preached to you, let him be accursed. As we have said before, so now I say again, if anyone preaches any other gospel to you than what you have received, let him be accursed. For do I now persuade men, or God? Or do I seek to please men? For if I still pleased men, I would not be a bondservant of Christ" (Galatians 1:6-10).
There is only one faith given by God.
"I, therefore, the prisoner of the Lord, beseech you to walk worthy of the calling with which you were called, with all lowliness and gentleness, with longsuffering, bearing with one another in love, endeavoring to keep the unity of the Spirit in the bond of peace. There is one body and one Spirit, just as you were called in one hope of your calling; one Lord, one faith, one baptism; one God and Father of all, who is above all, and through all, and in you all" (Ephesians 4:1-6).
Unity can only come by teaching the one doctrine of God because there is only one God, but many men who have many ideas.
False teaching is a fact of life in this world. "Beloved, do not believe every spirit, but test the spirits, whether they are of God; because many false prophets have gone out into the world" (I John 4:1). The hearer of the gospel has as much responsibility as the preacher of the gospel to make sure that what he is being taught is the message of God. This is why the Bereans were praised. "These were more fair-minded than those in Thessalonica, in that they received the word with all readiness, and searched the Scriptures daily to find out whether these things were so" (Acts 17:11). You have a mind and a Bible; use them to sort out the truth from the lies.