Muhammad bin Abdullah Rasulullah Sallallahu Alaihi Wasallam
One day Rasulullah s.a.w slept with his wife Siti Aishah r.a. When the middle of the night Prophet Muhammad S.a.w get up for Qiamulail. Before he got up from bed, he asked permision from his wife.
(This shows the attitude of the noble Prophet).
He get up and going to the toilet and get ablution. After that he get a solat and up his hand for pray and also cry. He do that until Bilal r.a had told him will dawn prayer sounded shortly.
His wife Aishah r.a asked him. Ya Rasulullah, why u do this while Allah forgives your sins past and future.
Prophet Muhammad s.a.w said, i want to be a grateful slave. Riwayat ibnu Hibban