Isaiah 41:17

When the poor and needy seek water - Water is often used in the Scriptures as an emblem of the provisions of divine mercy. Bursting fountains in a desert, and flowing streams unexpectedly met with in a dry and thirsty land, are often also employed to denote the comfort and refreshment which the gospel furnishes to sinful and suffering man in his journey through this world. The ‘poor and needy’ here, doubtless refer primarily to the afflicted captives in Babylon. But the expression of the prophet is general, and the description is as applicable to his people at all times in similar circumstances as it was to them. The image here is derived from their anticipated return from Babylon to Judea. The journey lay through a vast pathless desert (see the notes at Isaiah 40:3). In that journey when they were weary, faint and thirsty, God would meet and refresh them as if he should open fountains in their way, and plant trees with far-reaching boughs and thick foliage along the road to produce a grateful shade, and make the whole journey through a pleasant grove. As he met their fathers in their journey from Egypt to the land of Canaan, and had brought water from the flinty rock in the desert (Exodus 15:22 ff), so in their journey through the sands of Arabia Deserta, he would again meet them, and provide for all their want.