Unity of Believers

One of the primary reasons that unity among believers is so important, is that unity in the church points to unity in the Godhead. God the Father, God the Son and God the Holy Spirit always work together as one - and so should we. Unity is so important to Jesus that the longest recorded prayer that He prays in the Bible is for the unity of believers.
"My prayer is not for them alone. I pray also for those who will believe in me through their message, 21 that all of them may be one, Father, just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me. " (John 17: 20-21)