The Messenger of Allah ﷺ said, "What I fear most for my community is associating partners with Allah. I do not mean that they will worship the sun, the moon, or idols, but rather that they will perform deeds for other than Allah, along with hidden desire."
حدثنا محمد بن خلف العسقلاني حدثنا رواد بن الجراح عن عامر بن عبد الله عن الحسن بن ذكوان عن عبادة بن نسي
قال رسول الله ﷺ إن أخوف ما أتخوف على أمتي الإشراك بالله أما إني لست أقول يعبدون شمسا ولا قمرا ولا وثنا ولكن أعمالا لغير الله وشهوة خفية
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[Daif] Rawwad was truthful but became confused toward the end of his life and was therefore abandoned, and his hadith from Thawri contains severe weakness (Taqrib). Amir bin Abdullah is unknown (also Taqrib). Hasan bin Zakwan was truthful but made mistakes, was accused of holding the view of predestination denial (qadr), and used to practice tadlis (also Taqrib). It has two corroborating narrations, both extremely daif (Mishkat, no. 5332, in my edition).