A reader writes:
Contrary to your reader, John the Baptist and James the brother of Jesus were life-long Nazirites, so not only did they have beards, they never shaved. Paul didn't say: "that long hair on a man was a shame", but "Does not nature itself teach you that if a man wears long hair it is a disgrace for him", after saying in the same book (1 Corinthians): "The natural person does not accept the things of the Spirit of God, for they are folly to him...". Paul himself in Acts is described twice as taking short term Nazarite vows. You could interpret Matthew 26:29 "I tell you I will not drink again of this fruit of the vine until that day when I drink it new with you in my Father's kingdom" as Jesus taking a Nazarite vow, and so also not cutting his hair or beard.
You could point to Isaiah 50:6 as an argument for Jesus having a beard. "I offered my back to those who beat me, my cheeks to those who pulled out my beard; I did not hide my face from mocking and spitting."
A minor but important point: Jesus was a Jew. More importantly, he was involved in or around the Essene sect of John the Baptist and other ultra-religious, almost fanatically observant Jews. Among the most important tenets of this community was not shaving. It's the same biblical precept followed by the Hasidic sects today.
He was an adult, Jewish male. He had a beard.
I found this discussion especially funny because it started on the first day of Lent, which represents the 40 days Jesus spent in the desert. I'd put my money on Jesus having a beard, certainly by day 40.
In the Byzantine representations of Jesus, you will see him with a beard as the human, suffering Jesus, and then beardless as the everlasting Christ ruling in Heaven.
People have always imagined Jesus in their own image. It isn't correct to say that the earliest portraits show him in the style of Zeus - the earliest known portrait is from the early 3rd century AD and shows him as a beardless young philosopher - not a (son of) god, but a revered wise man. To quote from Wikipedia:
The oldest known portrait of Jesus, found in Syria and dated to about 235, shows him as a beardless young man of authoritative and dignified bearing. He is depicted dressed in the style of a young philosopher, with close-cropped hair and wearing a tunic and pallium signs of good breeding in Greco-Roman society. From this, it is evident that some early Christians paid no heed to the historical context of Jesus being a Jew and visualised him solely in terms of their own social context, as a quasi-heroic figure, without supernatural attributes such as a nimbus (a fourth-century innovation).
See the depiction here and note the lack of stubble! The beard didn't come along until the late 4th century. Here's what it looked like then. Much more on this here. It's a bit sobering, though, to think that the oldest known depiction of Jesus (as opposed to a portrait) is an anti-Christian graffito that may be as old as the 1st or possibly the 2nd century AD - it shows Jesus as a crucified donkey.
Another says of the above image, "From a recent Facebook discussion of the image of Jesus over time."