Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) says that the Prophet (peace and blessings be upon him) said to Sayyidah Asma (may Allah be pleased with her): "Why do I see the bodies of my nephews so thin? Are they suffering some hardship?" She said: "There is no hardship; it is only that the evil eye strikes them quickly. Shall I perform ruqyah for them?" He (peace and blessings be upon him) asked: "With what?" So she recited some words to him (peace and blessings be upon him), and he (peace and blessings be upon him) said: "Perform ruqyah for them with it."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19593