Unity of the Spirit for believers is very important to God. But this is not the same as the spirit of unity found among some of the more conservative groups of Christians today.
True unity is based on truth.
If a group of Christians are unified on anything other than truth, there is not true unity. In fact, Jesus is the Truth, and He is the foundation. And you must conform to all the teachings and practices of the church, which, in all cases of which I am aware, are an admixture of truth and tradition and false doctrine. In other words unless you accept all their teaching as the truth you are not submitting to a spirit of unity. First of all, after being born again, you must be filled with the Holy Spirit.