And the sixth, Ithream, by Eglah David's wife. These were born to David in {c} Hebron.

(c) Within seven years and six months.

Wesley's Notes

3:5 Eglah - This is added, either because she was of obscure parentage, and was known by no other title but her relation to David: or, because this was his first and most proper wife, best known by her other name of Michal, who, though she had no child by David after she scoffed at him for dancing before the ark, chap.6:23, yet might have one before that time. And she might be named the last, because she was given away from David, and married to another man. Six sons in seven years. Some have had as numerous an offspring, and with much more honour and comfort, by one wife. And we know not that any of the six were famous: but three were very infamous.

Jamieson-Fausset-Brown Bible Commentary

5. Eglah David's wife-This addition has led many to think that Eglah was another name for Michal, the first and proper wife, who, though she had no family after her insolent ridicule of David (2Sa 6:23), might have had a child before.

Matthew Henry's Concise Commentary

3:1-6 The length of this war tried the faith and patience of David, and made his settlement at last the more welcome. The contest between grace and corruption in the hearts of believers, may fitly be compared to this warfare. There is a long war between them, the flesh lusting against the spirit, and the spirit against the flesh; but as the work of holiness is carried on, corruption, like the house of Saul, grows weaker and weaker; while grace, like the house of David, grows stronger and stronger.