The Messenger of Allah ﷺ said, "The worst kind of thief among people is the one who steals from his prayer."They asked, "Messenger of Allah, how does he steal from it?"He replied, "By not completing its bowing and prostration."
حدثنا عفان حدثنا حماد أخبرنا علي بن زيد عن سعيد بن المسيب
أن رسول الله ﷺ قال إن أسوأ الناس سرقة الذي يسرق صلاته قالوا يا رسول الله وكيف يسرقها قال لا يتم ركوعها ولا سجودها
Its chain of transmission is hasan. As for Ali bin Zayd bin Jadan, we have often favored regarding his hadith as hasan, as noted before. Haythami said in 2/120, "It contains Ali bin Zayd, and there is disagreement over relying on him as evidence, while the rest of its narrators are the narrators of the Sahih." He did not wish to weaken it or state that explicitly. Hakim graded it sahih in 1/229, and Dhahabi agreed with him. It is also found in Bayhaqi 2/386 and Ibn Abu Shayba 1/288, in the chapter on prayer, "The man who diminishes his prayer."