Sayyiduna Abu Qatadah (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) said: "The worst thief among people is the one who steals from his prayer." The people submitted, "O Messenger of Allah, how does he steal from his prayer?" The Prophet (peace and blessings be upon him) said: "He does not complete its ruku' (bowing) and its sujud (prostrations)" (or the narrator is unsure and the words are perhaps:) "He does not straighten his back in ruku', nor in sujud."
Imam Ahmad recorded this narration, and Imam al-Tabarani in al-Mu'jam al-Kabir and al-Mu'jam al-Awsat, and its narrators are the narrators of the Sahih.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2719
Hadith Gradingمحدثین:إسنادہ صحیح۔
Hadith Takhrij«أخرجه مسند أحمد برقم: 22136، وأخرجه سنن الدارمي برقم: 1328، وأخرجه المستدرك على الصحيحين برقم: 867، وأخرجه صحيح ابن خزيمة برقم: 663، وأخرجه المعجم الكبير للطبراني برقم: 3283، وأخرجه المعجم الأوسط للطبراني برقم: 8175»