I simply offer this as food for thought. Being a follower of Christ myself, I am always amazed at the way a self-proclaimed agnostic like Mark Twain was so gifted at seeing the struggles of being a Christ follower, which might be why he never became one himself. This passage eloquently explains the tension I feel within my own heart and why I find following Christ so challenging.
“A man can be a Christian or a patriot, but he can’t legally be a Christian and a patriot — except in the usual way: one of the two with the mouth, the other with the heart. The spirit of Christianity proclaims the brotherhood of the race and the meaning of that strong word has not been left to guesswork, but made tremendously definite — the Christian must forgive his brother man all crimes he can imagine and commit, and all insults he can conceive and utter- forgive these injuries how many times? — seventy times seven — another way of saying there shall be no limit to this forgiveness. That is the spirit and the law of Christianity. Well — Patriotism has its laws. And it also is a perfectly definite one, there are not vaguenesses about it. It commands that the brother over the border shall be sharply watched and brought to book every time he does us a hurt or offends us with an insult. Word it as softly as you please, the spirit of patriotism is the spirit of the dog and wolf. The moment there is a misunderstanding about a boundary line or a hamper of fish or some other squalid matter, see patriotism rise, and hear him split the universe with is war-whoop. The spirit of patriotism being in its nature jealous and selfish, is just in man’s line, it comes natural to him — he can live up to all its requirements to the letter; but the spirit of Christianity is not in its entirety possible to him.
The prayers concealed in what I have been saying is, not that patriotism should cease and not that the talk about universal brotherhood should cease, but that the incongruous firm be dissolved and each limb of it be required to transact business by itself, for the future.”
– Mark Twain’s Notebook