What are you doing, my son? What are you doing, son of my womb? What are you doing, son of my vows?
Most interpreters are of opinion that Lemuel is Solomon; the name signifies one that is for God, or devoted to God; and so it agrees well enough with that honourable name which, by divine appointment, was given to Solomon (Sa2 12:25), Jedediah - beloved of the Lord.
Commenting on Proverbs 31:1-9
What, my son?.... What shall I call thee? though thou art a king, can I address thee in more suitable language, or use a more endearing appellative than this, and what follows? permit me, thy mother, to speak unto thee as my son: and what shall I say to thee?
What, my son?--that is, What shall I say? Repetitions denote earnestness. son of my womb--as our phrase, "my own son," a term of special affection. son of my vows--as one dedicated to God; so the word "Lemuel" may mean.