Zechariah 14:8

And it shall be in that day, [that] living waters shall go
out from Jerusalem
When it shall be light; and this is one of the things which will make it so; for by "living waters" are meant the Gospel, and the doctrines of it; compared to running "waters" for the sound of them, which will then go into all the earth; for the swiftness in which they shall proceed; for their rapidity and force in bearing all before them; for the great spread of them; and for their virtue and efficacy in cooling those who are inflamed with the fiery law; refreshing thirsty souls; purifying the hearts and lives of sinners, and making those that are barren fruitful: and to "living" waters, because they are the means of quickening dead sinners, and of reviving drooping saints; and because they serve to support and maintain a spiritual life, and nourish up unto eternal life, and direct the way to it, as well as give the best account of it: and these will come out of Jerusalem; which may design Jerusalem literally, which will be rebuilt at the time of the Jews' conversion; or mystically the church, the spiritual and heavenly Jerusalem; see ( Hebrews 12:22 ) ( Ezekiel 47:1 ) ( Joel 3:18 ) reference seems to be had to the first ministration of the Gospel, which, according to prophecy, came out of Jerusalem, ( Isaiah 2:3 ) .

Half of them towards the former sea;
or the eastern sea, as the Targum, the Persian sea; and may signify that the Gospel shall be carried into the eastern parts of the world, into Persia, Tartary, and China, and other nations; and those great kingdoms shall become the kingdoms of Christ:

and half of them toward the hinder sea;
or the western sea, as the Targum, the Mediterranean Sea; and may denote the progress and success of the Gospel in the European parts of the world: and the meaning of the whole is, that the Gospel shall be carried from east to west, and preached all the world over, to the conversion of Jews and Gentiles, who, some think, are designed by the two seas; when the abundance of the sea shall be converted by it, and the forces and fulness of the Gentiles brought in, and all Israel saved:

in summer and in winter shall it be;
there will be no summer of persecution, nor winter of coldness and indifference to hinder the ministry of the word: the phrase denotes the constant ministry of the word, and the duration of it; it shall be constantly preached all the year long, and as long as summer and winter last.