'Within' in the Bible

Then they came near, and spoke before the king concerning the king's decree: Haven't you signed an decree, that every man who shall make petition to any god or man within thirty days, except to you, O king, shall be cast into the den of lions? The king answered, The thing is true, according to the law of the Medes and Persians, which doesn't alter.

Then shall stand up in his place one who shall cause a tax collector to pass through the kingdom to maintain its glory; but within few days he shall be destroyed, neither in anger, nor in battle.