This idiom is used to introduce a special message from God. See how you translated this in [Haggai 1:1](./01.md). AT: "Yahweh gave a message" or "Yawheh spoke this message" (See: [[rc://en/ta/man/translate/figs-idiom]])
Here the word "hand" refers to Haggai himself. Yahweh used Haggai as the agent to deliver his command. See how you translated this in [Haggai 1:1](./01.md). AT: "through Haggai" (See: [[rc://en/ta/man/translate/figs-synecdoche]])