A. Not being able to work together:

AMO 3:3. Can two walk together, except they be agreed?

ACT 15:36. And some days after Paul said unto Barnabas, Let us go again and visit our brethren in every city where we have preached the word of the LORD, and see how they do.

ACT 15:37. And Barnabas determined to take with them John, whose surname was Mark.

ACT 15:38. But Paul thought not good to take him with them, who departed from them from Pamphylia, and went not with them to the work.

ACT 15:39. And the contention was so sharp between them, that they departed asunder one from the other: and so Barnabas took Mark, and sailed unto Cyprus;

ACT 15:40. And Paul chose Silas, and departed, being recommended by the brethren unto the grace of God.

B. It destroys God's work:

MAT 12:25. And Jesus knew their thoughts, and said unto them, Every kingdom divided against itself is brought to desolation; and every city or house divided against itself shall not stand:

MAR 3:24. And if a kingdom be divided against itself, that kingdom cannot stand.

C. Longstanding divisions:

PRO 18:19. A brother offended is harder to be won than a strong city: and their contentions are like the bars of a castle.

D. Creates sectarian divisions & man-worship:

1COR 3:3. For ye are yet carnal: for whereas there is among you envying, and strife, and divisions, are ye not carnal, and walk as men?

1COR 3:4. For while one saith, I am of Paul; and another, I am of Apollos; are ye not carnal?

1COR 11:18. For first of all, when ye come together in the church, I hear that there be divisions among you; and I partly believe it.

E. Backbiting & rumours:

PRO 16:28. A froward man soweth strife: and a whisperer separateth chief friends.

2COR 12:20. For I fear, lest, when I come, I shall not find you such as I would, and that I shall be found unto you such as ye would not: lest there be debates, envyings, wraths, strifes, backbitings, whisperings, swellings, tumults:

F. Opens the door to every kind of evil: