The shower to come down - The Holy Spirit's influence.

There shall be showers of blessing - Light, life, joy, peace, and power shall be manifest in all the assemblies of Christ's people.

they shall. It is evident that this prophecy could at most have only a typical accomplishment in the return from captivity under Zerubbabel, and in their consequent prosperity; but the restoration of the Jews from their present captivity, and the consequent peace and prosperity of the church and world, fully answer to this energetic language.

Ezekiel 34:8 As I live, said the Lord GOD, surely because my flock became a prey, and my flock became meat to every beast of the field...

Ezekiel 36:4 Therefore, you mountains of Israel, hear the word of the Lord GOD; Thus said the Lord GOD to the mountains, and to the hills...

neither

Ezekiel 34:25,29 And I will make with them a covenant of peace, and will cause the evil beasts to cease out of the land...

Jeremiah 30:10 Therefore fear you not, O my servant Jacob, said the LORD; neither be dismayed, O Israel: for, see...

Jeremiah 46:27 But fear not you, O my servant Jacob, and be not dismayed, O Israel: for, behold, I will save you from afar off...

The Good Shepherd' and his one Flock' - Last Discourse at the Feast of Tabernacles.
The closing words which Jesus had spoken to those Pharisees who followed HIm breathe the sadness of expected near judgment, rather than the hopefulness of expostulation. And the Discourse which followed, ere He once more left Jerusalem, is of the same character. It seems, as if Jesus could not part from the City in holy anger, but ever, and only, with tears. All the topics of the former Discourses are now resumed and applied. They are not in any way softened or modified, but uttered in accents of …
Alfred Edersheim—The Life and Times of Jesus the Messiah

That the Ruler Should Be, through Humility, a Companion of Good Livers, But, through the Zeal of Righteousness, Rigid against the vices of Evildoers.
The ruler should be, through humility, a companion of good livers, and, through the zeal of righteousness, rigid against the vices of evil-doers; so that in nothing he prefer himself to the good, and yet, when the fault of the bad requires it, he be at once conscious of the power of his priority; to the end that, while among his subordinates who live well he waives his rank and accounts them as his equals, he may not fear to execute the laws of rectitude towards the perverse. For, as I remember to …
Leo the Great—Writings of Leo the Great

Covenanting Provided for in the Everlasting Covenant.
The duty of Covenanting is founded on the law of nature; but it also stands among the arrangements of Divine mercy made from everlasting. The promulgation of the law, enjoining it on man in innocence as a duty, was due to God's necessary dominion over the creatures of his power. The revelation of it as a service obligatory on men in a state of sin, arose from his unmerited grace. In the one display, we contemplate the authority of the righteous moral Governor of the universe; in the other, we see …
John Cunningham—The Ordinance of Covenanting