We went out with God’s Messenger one night and came upon a man who made supplication with persistence. The Prophet said, “He will have done something which guarantees if he puts a seal to it.” One of the people asked what he should use for a seal, and he replied, “Amen”.
When I was leading God’s Messenger’s she-camel for him on a journey he said to me, “Shall I not teach you, ‘Uqba, the best two suras to recite?” Then he taught me “Say, I seek refuge in the Lord of the dawn” and “Say, I seek refuge in the Lord of men” (Al-Qur’an; 113-114). He saw that I was not greatly pleased with them, so when he alighted for the Morning Prayer he used them in leading the people in the Morning Prayer, and when he had finished he turned to me and said, “How do you find them now, ‘Uqba?”
Wa’il b. Hujr said that he heard God’s Messenger recite, “Not of those with whom Thou art angry, nor of those who go astray” (Al-Qur’an 1:7) and say “Amen”, prolonging the word.
Tirmidhi, Abu Dawud, Darimi and Ibn Majah transmitted it.