en_tn_condensed/zep/03/16.md

In that day

"At that time" or "When this happens." This phrase here refers to the time of peace and restoration that immediately follows the day of Yahweh.

say to Jerusalem ... Zion

The names of these cities here refer to the people who live in them. Alternate translation: "say to the people of Jerusalem ... people of Zion" (See: rc://en/ta/man/jit/figs-metonymy)

Do not let your hands become weak

Here the "hands" are a metonym for the whole person and being physically weak is a metaphor for being discouraged. Alternate translation: "Do not allow yourself become weak" or "Do not become discouraged and so stop working" (See: rc://en/ta/man/jit/figs-metaphor and rc://en/ta/man/jit/figs-synecdoche)