Tamim bin Tarafah narrates from Sayyiduna Jabir bin Samurah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Some people must certainly stop raising their gazes in prayer, or else their gazes will not return to them."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1808