The rain of your land, i.e. which is needful and sufficient for your land; or which is proper to your land, not common to Egypt, where, as all authors agree, there is little or no rain.
The first rain and the latter rain; the first fell in seed time, to make the corn spring, the other a little before harvest, to ripen it. See Jer_5:24Joe_2:23Amo_4:7Jam_5:7.