בְּנֵי֙ שֵׁלָ֣ה בֶן־יְהוּדָ֔ה עֵ֚ר אֲבִ֣י לֵכָ֔ה וְלַעְדָּ֖ה אֲבִ֣י מָרֵשָׁ֑ה וּמִשְׁפְּח֛וֹת בֵּית־עֲבֹדַ֥ת הַבֻּ֖ץ לְבֵ֥ית אַשְׁבֵּֽעַ׃
The sons of Shelah the son of Judah: Er the father of Lecah, and Ladah the father of Mareshah, and the families of the house of them that wrought fine linen, of the house of Ashbea;
Read kabbalistic (mystical) interpretation of I Chronicles 4:21: and classical mystical sources.