The Pulpit Commentary on Psalms 107:3

And gathered them out of the lands (compare the prayer of Psalms 106:47; and for the expression, "the lands"—i.e. the foreign countries—see Psalms 106:27; Ezra 9:1). From the east, and from the west, from the north, and from the south.

The present Hebrew text has מִיָּם, "from the sea" and so the LXX; ἀπὸ θαλάσσης—but it is thought that probably מִיָּם is a corruption of מִיָּמִין (Cheyne), which would mean "from the south."