It is likely you have a line or two, which even if you do from memory, may be found on the net. Again, you may use a perfectly legal quote which, if on the net, they will reject it.
You can change the quote significantly or remove it. If you change it, then give credit to the author and say that you have paraphrased that part.
Perhaps it is better to ask what the real problem is. Are you using quotes? If its only the poem, then a line or sentence may be inadvertently on the net. Easily done as you are a religious man.
I know so many stuff in my head from being a keen christian in my youth. But yes, this days they can be found on the net, and this might be where your trouble lies. Much Love.