The sons of Shelah son of Judah: Er the father of Lecah, Laadah the father of Mareshah and the clans of the linen workers at Beth-ashbea,
We may observe in these verses, 1. That here is a whole family of craftsmen, handicraft tradesmen, that applied themselves to all sorts of manufactures, in which they were ingenious and industrious above their neighbours, Ch1 4:14. There was a valley where they lived which was, from them, called the valley of craftsmen. Those that are craftsmen are not therefore to be looked upon as mean men.
Commenting on 1 Chronicles 4:11-23
The sons of Shelah, the son of Judah, were,.... The genealogy of the posterity of Judah, in the lines of Pharez and Zerah, being given, and very largely in that of the former, because of the honour of David, and his kingdom, which sprang from thence, as Jarchi observes, and also the King Messiah, the writer returns to give an account of his posterity by...
POSTERITY OF SHELAH. (Ch1 4:21-23) Laadah . . . the father . . . of the house of them that wrought fine linen--Here, again, is another incidental evidence that in very early times certain trades were followed by particular families among the Hebrews, apparently in hereditary succession.