The duality of religion/spirituality in society makes such a deep-rooted part of human life also so taboo it is often banned from acceptable topics of conversation. The deeply personal beliefs and influence religion/spirituality has on the lives of its followers along with the sense of community it can create can also foster an us vs. them mentality, escalating conflict to violence in far too many cases.
But as time marches forward and science is able to answer more questions and find more solutions to natural and technological problems, the hold religion has had on humanity is starting to wane, at least in developed nations. This isn't to say spirituality is on the decline, but the ubiquity of a powerful and at times prejudicial and abusive organized religion dictating the ins and outs of individuals and society at large is struggling to stay afloat.
With religiosity decreasing, agnosticism and atheism on the rise, and the strong nexus of political leaning and religious implication on full display, the clashing of different factions is palpable and public. So how do we love thy neighbor despite having very different beliefs?
First, it is important to understand what you're dealing with, and define what religious, spiritual, agnostic and atheist are.
Religious: A follower of a recognized system of faith typically based around a deity or group of deities, usually called a religion. A regular participant in the rites, rituals and practices of an organized religion.
Spiritual: A believer in a power, or system of powers, greater than themselves that has jurisdiction over the physical world, to a degree. The belief in the interconnectedness of all things, including that which is beyond what can be identified by the 5 senses, often referred to as a metaphysical realm or astral plane.
Agnostic: The questioning, doubt, or non-belief in a deity, greater power, or realm of reality beyond what can be identified by the 5 senses.
Atheist: Classic definition - someone who does not follow a recognized system of faith or organized religion. Modern meaning - a catchall for someone who does not believe in a deity or an all powerful creator, often misconstrued with agnostic. It is mostly associated with monotheistic religions, such as Christianity, Judaism and Islam. It may not apply to polytheistic beliefs like Hinduism, or other systems of faith not considered religions like Buddhism.
What many faiths have in common is the importance of the personal connection and individual relationship with their higher power. Each person walks their own road with and to their deity , and their soul's path is unique to them. An atheist need only remove the higher power from this idea to have a similar relationship with their own existence. Each person's life is their own and they must follow their own path to whatever they seek; enlightenment, peace, success, power, or perhaps even faith. There is no need to justify or prove your path to another, as the most important relationship is with your higher power, or yourself. Other people may guide or accompany you but the journey is yours.
With so many systems of faith in the world there are bound to be conflicts. Some as small as what foods can or can't be eaten, or as significant as who is an is not valued as a human being and permitted to live. But while each religion or spiritual sect may have different values, beliefs and rituals, the foundation of each faith is usually that of personal connection to their deity, duty of community, and love of man and greater power. This isn't always the case, but while details differ the main ideals tend to be similar. And atheists can also live by these foundations of connection, duty and love.
Too often devout and overzealous people tend to exploit any opportunity they get to spout their dogma at any willing or unwilling listener. Just about all conversations and interactions get funneled into a lecture or sermon on their beliefs. And inevitably the compulsion to covertly or overtly convert others to their side can overtake some who don't recognized or respect other's boundaries. Whether trying to convince another of the fallacy of faith or the righteousness of religion, it is both uncomfortable and boring to be around someone who is only interested in getting their point across on a singular subject.
It is perfectly fine to have religious debates or share your spiritual experiences. But they don't need to become shouting matches, character assassinations or targeted campaigns. Speak softly, listen more than you speak, and view people as whole and complex, not an extension or representation of their faith.
The rift between different religions can be as wide as the chasm between belief and non-belief. And remaining outside of the realm of faith doesn't save all atheists or agnostics from the pitfalls and missteps of the spiritually overzealous. We may not agree on many things, and it can be hard to see followers of a faith that wishes to reject and persecute us as worthy of respect. But deep down almost all people want the same thing. We need love, safety, community, acceptance, and room to grow. It may take a concerted effort to evolve the personal interplay of faith in one's life to this level. But it would strengthen our own ties to a greater power and each other if we could manage to embrace even those we wish to leave alone.