The King of Assyria (through his messenger Rabshakeh) does not ask these questions looking for an answer, but wants to make King Hezekiah doubt himself and Egypt's support. AT: "Do not trust in anybody. You were foolish to rebel against me." (See: [[rc://en/ta/man/translate/figs-rquestion]])
The King of Assyria compares Egypt to a weak walking stick; you expect that it will support you when you lean on it, but instead it breaks and cuts you. AT: "the weak support from Egypt" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The speaker is extending the metaphor by describing what happens when a reed is used as a support. AT: "but if someone uses this for support, he will be injured" (See: [[rc://en/ta/man/translate/figs-metaphor]])