Here Yahweh speaks of Moab as if it were a man. Here it represents the people of Moab. All occurrences of "he," "his," and "him" in 48:11-12 can be stated as "they," "their," or "them." Alternate translation: "Even from their earliest times, the people of Moab have always felt secure ... They are ... their wine ... send them" (See: [[rc://en/ta/man/translate/figs-personification]])
For wine to taste good, it has to be left undisturbed for a long time and not poured from one pot to another. Yahweh compares the people of Moab, who are prosperous because no one has ever conquered them and taken them as captives, to wine that is undisturbed and has a good flavor. (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/figs-simile]])