The Messenger of Allah ﷺ used to say: "Whoever prays four rak'ahs before Zuhr and four after, Allah, the Mighty and Sublime, will forbid him from the Fire." (Using translation from Nasāʾī 1814)
أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ «مَنْ حَافَظَ عَلَى أَرْبَعِ رَكَعَاتٍ قَبْلَ الظُّهْرِ وَأَرْبَعٍ بَعْدَهَا حَرَّمَهُ اللَّهُ عَلَى النَّارِ»