A high ranking captain who was the king's personal assistant is spoken of as if he was a person on whom the king leaned his hand. Alternate translation: "the captain who was close to the king" or "the captain who was the king's personal assistant" (See: [[rc://en/ta/man/jit/figs-metaphor]])
Yahweh causing much rain to fall in order to make the crops grow is spoken of as if Yahweh were opening windows in heaven through which he pours down rain. Alternate translation: "even if Yahweh were to cause much rain to fall from heaven" (See: [[rc://en/ta/man/jit/figs-metaphor]])
The captain asks this question to express his unbelief. This rhetorical question can be translated as a statement. Alternate translation: "this could never happen!" (See: [[rc://en/ta/man/jit/figs-rquestion]])
The phrase "with your own eyes" emphasizes that the captain will certainly see the things that Elisha prophesied. Alternate translation: "you yourself will watch these things happen" (See: [[rc://en/ta/man/jit/figs-synecdoche]])