Sayyiduna Abu Qatadah (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) said: "The worst thief among people is the one who steals from his prayer." The companions asked, "O Messenger of Allah, how does he steal from his prayer?" He (peace and blessings be upon him) replied: "He does not complete its bowing (ruku') and prostration (sujud)."