What is the meaning of Malachi 3:17?

* The two F.O.G. Bibles & Commentary below are currently a work in progress.

“They will be Mine,” says the LORD of Hosts, “on the day when I prepare My treasured possession. And I will spare them as a man spares his own son who serves him.

Berean Standard Bible (BSB)

They shall be mine,” says Yahweh of Armies, “my own possession in the day that I make, and I will spare them, as a man spares his own son who serves him.

World English Bible (WEB)

And they shall be mine, saith{H559}{(H8804)} the LORD{H3068} of hosts{H6635}, in that day{H3117} when I make up{H6213}{(H8802)} my jewels{H5459}; and I will spare{H2550}{(H8804)} them, as a man{H376} spareth{H2550}{(H8799)} his own son{H1121} that serveth{H5647}{(H8802)} him.

Strong's King James

(17) "And they will be Mine," says יהוה Yahweh-Tzva'ot, "unto the day that I make a special treasure and I will have compassion on them as a man has compassion on his own son serving אֵת him."

The F.O.G*

The F.O.G Paraphrase

And they have been to Me, said Jehovah of Hosts, In the day that I am appointing—a peculiar treasure, And I have had pity on them, As one hath pity on his son who is serving him.

Young's Literal Translation