As to why I believe denominations are good, religious freedom good, right to conscience good, a one Holy truth may start out with good intentions but as explained over time selfishness, pride, ignorance and sin can easily corrupt it. And if diversity isn't allowed then this one holy religion can become the truth seekers nightmare. Freedom of diversity protects against that. I believe our current denominational system is the best system within a fallen, broken, sinful world that still will have flaws from our fallen human nature. But by large it has protected the liberty and freedom of religion for centuries.