The Prophet ﷺ said, "Perform the bowing and the prostrations properly. By Allah, I see you from behind me (or from behind my back) when you bow or prostrate." (Using translation from Bukhārī 742)
"أقيمُوا الرُّكوعَ والسُّجُود، فوالله إني لأراكُمْ مِن بعد ظَهْرِي إذا ركَعُتمْ وإذا سَجَدْتُمْ".