Religions borrow from one another. So do scientific theories, political ideologies, musicians, and all human cultures and their expressions. We also have a great many shared symbols as human beings, which means that not every similarity indicates borrowing. Failure to recognize the last point is what Sandmel famously called “parallelomania.”
One instance of borrowing and of deep similarity of outlook and system across a wide diversity of details is, rather ironically, the meme that will not die claiming that Jesus was simply invented through a compilation of features popular among deities. Anyone remotely familiar with the relevant primary sources and/or scholarship about them will immediately spot the first problem, namely that Jesus did not start out as a deity. But beyond that, the alleged parallels consistently turn out after closer investigation to either not exist, be late additions to one or both traditions, or to be so general that countless figures human and divine are said to share them.
Unfortunately no matter how many times this is addressed it continues to circulate. Looking up the specific version that was mentioned in a Facebook comment recently, I found an incredibly detailed blog survey of this topic. It’s author Noah Edmonds concludes, “there is absolutely no evidence to suggest that a plethora of gods and ancient practices were thrown together all willy-nilly by a group of first century Jews who wanted to deceive people or trick them into following their poorly coded astrological cult. Many Jesus mythicists make the above assertions with boldness, assuming that the scholarly consensus is on their side and that they are taking the most logical standpoint. When someone makes such a claim, however, all it does is help to severely undermine their credibility, and show that they are either incapable of basic research skills, or refuse to do any research to begin with…”