There are two aspects to this question. Legal and social. The Jewish legal take on this I’d like to save for later, but I can tell you that it’s not 100% clearly forbidden, although there is a solid basis to not do it.
The more interesting and decisive factor in my personal experience is the social and philosophical aspect of a man with ear piercing. First of all it is definitely frowned upon in the religious world for a man to pierce his ear, since it is not the norm for men throughout history to do this.
But let me share a personal experience with you. A number of years ago I was teaching a class to a group of students with little or no Jewish educational background. It was in a “regular” Yeshiva, but the atmosphere was extremely tolerant and non-judgmental of how people looked, dressed and acted (as long as no red lines were crossed, such as creating a public disturbance with clearly immoral behavior).
One of the students in the class was wearing an earring.
We were studying the mitzvah of what to do with a Jewish indentured servant who refused to leave the house of his “master” when the period of his service was completed. The Torah states, “He will be brought to the doorpost and his master will bore his ear with an awl, and he shall serve him forever.” (Ex. 21:6) This is the punishment given to him for not wanting to leave the house to be on his own and work for himself, but rather continue to “serve” another person. As our Sages explain, “The ear which heard My voice on Mount Sinai saying: ‘For unto Me the children of Israel are servants; they are My servants,’ and not servants of servants — and this individual went and acquired for himself a master?! He will have his ear pierced.”
The next day the student who came with an earring on the previous day showed up to class without it. No one said a word about it and we continued our studies, but obviously the student understood an important lesson from the previous day’s class.
Regarding the Jewish legal aspect of a man wearing an earring, which I said in the beginning I would address later: “later” is now. A verse in the Torah that states, “A man should not wear a woman’s garment” (Deut. 22:5) is interpreted by Jewish law in a wider sense. Not only a woman’s clothing is intended, but also any item or act that is normally associated with a woman should not be done by a man. For example, a man should not try to beautify himself — for the sake of “beauty” — by removing a white hair that’s growing on his head of black hair. One reason given for this prohibition is that men should not try to look like women in order to mingle with them freely “as women” and come to commit immoral acts.
But regarding the legal (halachic) aspect of a man wearing earrings, I prefer to refrain from saying anything definitive, since every matter of Jewish law needs to be examined based on the very specific circumstances of the case by a competent authority.
