Secondly: Staying up night is light and remedy

 The prophet used to keep to staying up night because Allah says to him:

17-79: "During the night, you shall meditate for extra credit, that your Lord may raise you to an honorable rank."

Whoever wants to have a honorable rank, he should stay up night, Allah made it a duty for him, Allah says:

73-1, 2: "O you cloaked one. Meditate during the night, except rarely."

My master Ahmed Al-Badawey says about this: "Two prostrations in the second half of night are better than one thousand prostrations by day." Glory to Allah, modern science showed us the secret of night prayer as mentioned in the Hadeeth of: "You should keep to staying up night."