مِشْكَاةُ الْمَصَابِيحِ
Mishkat al-Masabih 1149
Prayer
The manner in which one who is led in prayer by an Imam must follow him, and the rule applying to the one who is preceded by him - Section 3
وَعنهُ قَالَ: الَّذِي يَرْفَعُ رَأْسَهُ وَيَخْفِضُهُ قَبْلَ الْإِمَامِ فَإِنَّمَا ناصيته بيد الشَّيْطَان ". رَوَاهُ مَالك
He said: If anyone raises and lowers his head before the imam, his forelock is in the devil’s hand. Malik transmitted it.
Mishkat al-Masabih, 1149ضَعِيف (الألباني)