Берешит 4:20 Комментарий: Rashi, Chizkuni, Rashbam & Radak

אבי יושב אהל ומקנה THE FATHER OF SUCH AS ABIDE IN TENTS AND OF SUCH THAT HAVE CATTLE — He was the first of those who pastured cattle, and he dwelt in tents, a month here and a month there, on account of the pasture necessary for his sheep; for when the grass was finished in one place he went away and pitched his tent in another place. There is a Midrashic statement (Genesis Rabbah 23:3) that he built temples for idol worship, (for ומקנה may be read ומקנה –– provoking jealousy), just as you say, (Ezekiel 8:3) "the image of jealousy which provoketh God to jealousy" (המקנה); similarly his brother handled the harp and guitar to make music for idol worship.

אבי יושב אהל ומקנה, “the original nomad living in tents” (instead of caves) as the owner followed his herds to where grazing was available. According to a Midrash quoted by Rashi, Yovol built houses to worship idols in. [This Midrash understands the word: מקנה, not as cattle, but as mekaneh, doing something to arouse jealousy, i.e. G-d’s jealousy. Ed.] His brother would then have been the first one to use musical instruments for the purpose of worshipping idols.

ישב אהל וקנה, this is another way of saying that he was a shepherd.