Anbasah narrates from Umm Habibah (may Allah be pleased with her) that she told Anbasah that the Prophet (peace and blessings be upon him) said: "Whoever guards four rak'ahs before Zuhr and four after it, that person is made forbidden to Hell."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4481