I will ... command - The parable is partly dropped and Jehovah, as in Isa 5:7, is implied to be the Owner: for He alone, not an ordinary husbandman (Mat 21:43; Luk 17:22), could give such a “command.”
no rain - antitypically, the heaven-sent teachings of the prophets (Amo 8:11). Not accomplished in the Babylonish captivity; for Jeremiah, Ezekiel, Daniel, Haggai, and Zechariah prophesied during or after it. But in gospel times.