'Shall I not direct you both to something better than a servant? When you go to bed say:'
سُبْحَانَ اللَّهِ
How Perfect Allaah is.
Subhaanallaahi
….thirty-three times
وَالْحَمْدُ لِلَّهِ
All praise is for Allaah.
Walhamdu lillaahi
...thirty-three times
وَاللَّهُ أَكْبَرُ
Allaah is the greatest.
Wallaahu 'akbar.
...thirty-four times...for that is indeed better for you both than a servant.
Al-Bukhari, Fathul Bari 7/71, Muslim 4/2091.