Charles Ellicott Commentary Isaiah 27:3

"I Jehovah am its keeper; I will water it every moment: lest any hurt it, I will keep it night and day." — Isaiah 27:3 (ASV)

I the Lord do keep it: The words imply a distinct reversal of the sentence passed in Isaiah 5:1-7. Instead of abandonment, there is constant care. Instead of the clouds being commanded to give no rain, the vineyard is watered whenever it requires watering. Instead of being wasted by the wild boar or by spoilers, Jehovah tends it both by day and night.