'Knee' in the Bible

Every hand will be limp. Every knee will glisten with sweat."

When they'll ask you, "Why are you groaning?' you are to say, "Because of the news that just arrived. Every heart will melt with fear, every hand will grow limp, every spirit will grow faint, and every knee will glisten with sweat.' Look! It has come and it will be fulfilled," declares the Lord GOD.