My doctrine shall drop as the rain As nothing is more grateful to the thirsty earth than gentle showers, so there cannot be any thing more acceptable to those who are desirous of knowing the divine will than the revelation of it. And as the dew and rain gently falling soften and refresh the earth, producing both verdure and fertility; so my doctrine, or the words I am going to speak, if received into people's minds in faith and love, will cause them to grow in grace and goodness, and produce the fruits of righteousness. Or it may be rendered, Let my doctrine drop, &c. Accordingly the learned Bishop Patrick understands this as a prayer, that his words, which were sent from heaven to them, might sink into their hearts and soften them, as the rain doth the earth, and so make them fruitful in obedience.
Related Commentaries of Deuteronomy 32:2
Deuteronomy 32:2
2 My doctrine shall drop as the rain, my speech shall distil as the dew, as the small rain upon the tender herb, and as the showers upon the grass: