Community harmony has its foundations laid in the common search for genuine understanding of the Truth by each of the community's inhabitants. This is a mythological foundation in the sense that it is impossible for any community to possess only members who really want to know the truth. Therefore, community harmony is impossible until the coming of Jesus.
But, even if it is impossible, those of us who really want to be guided by the Truth are living under a divine mandate to be at peace with all men as much as possible. So, understanding that I have a limited audience of Truth-seekers, I want to argue for some basics in seeking for the Truth. These basics are not dogmatic and inspired principles of a preacher to a reading audience. They are, rather, basics which the Bible says stand the test of eternity.
The first basic: seek God as He is and not as you want Him to be. People who assume their understanding of God is legitimate because their concept of Him fits their list of desired characteristics are going to be mightily disappointed when they stand before Him face to face. Note that 1 Corinthians 10:12 says "Wherefore let him that thinketh he standeth take heed lest he fall", which is a warning against intellectual arrogance. Note also that Isaiah 55:8 says "For my thoughts [are] not your thoughts, neither [are] your ways my ways, saith the Lord", which is a warning against intellectual assumptions. We are called by these two texts to be very careful that we do not impose upon God our intellectual arrogance and assumptions.
The second basic: hold loosely to the religion, or lack thereof, that has been passed on to you by others. How is anyone converted to Christ who refuses to hold lightly to the religion of others? Conversion (which is the foundation for real hope) is not achieved by buying into someone else's religion, but by coming mentally and emotionally into contact with God and putting our commitment and trust in Him.
The third basic: seek God through His self-revelation as given in Word and Deed. It goes without saying that no one will know God who does not hear from Him. It also goes without saying that no one will hear from Him who is not willing to listen to Him. It also goes without saying that no one will listen who has nothing to listen to: God has spoken in Word and Deed. The Bible says in Romans 1:19 that "... that which may be known of God is manifest in them; for God hath shewed [it] unto them." The apostle says the creation declares some things about God that we may know if we will look into what He has made. But, it also says in Romans 10:14 and 17, "How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher?...So then faith [cometh] by hearing, and hearing by the word of God." God has spoken in the pages of the Bible, written by divinely given preachers. We ignore it at our eternal peril.