Omar Ibn Al-Khattab said: " While I was in Medina one day, I saw "Thamama Ibn Athalin" idolater from Yamama, entering Medina with his Sword drawn. I approached Thamama and asked him: " What are you up to, Thamama?", Thamama said: " I'm looking for Mohammad to kill him!".
Omar said: " I grabbed Thamama and tied him up to a mosque's polar and went to inform the Prophet (pbuh) of what just happened."
When the prophet (pbuh) arrived to the mosque, many Muslims has gathered then, he approached Thamama and looked him straight in the face and then looked around to his followers and said: "did anybody bring him food?". Omar said: "No, O' Messenger of Allah!". The prophet said: "Abu Hurayra, go to my house and bring back some milk". Abu Hurayra came back with the milk and gave it to the Prophet (pbuh). The Prophet (pbuh) ordered Omar to untie Thamama. The Prophet (pbuh) extended his right hand that carries the cup of milk to Thamama, and said: " Drink, O' Thamama?"
After Thamama drank the milk, the Prophet (pbuh) said to Thamama: "Embrace Islam O' Thamama?", Thamama said: "NO". The Prophet (pbuh) asked again: " Say the testimony O' Thamama?", Thamama said: "NO". The Prophet said: "You can go, you're free".
After Thamama took few footsteps forward, he came back toward the Prophet (pbuh) and before him he said: " I bear witness that there is no God but Allah, and you Mohammad is the messenger of Allah". The Prophet asked, with big surprise on his face,: " What made you refuse Islam when I offered it to you?". Thamama said: " O'Messenger of Allah, when I came to Medina, you're the most hated person in my whole life, but now you're the most beloved person in my life." Thamama continued to say: " O'Messenger of Allah, when you offered me the Islam, I didn't accept it since I didn't want people to think that I embraced Islam for the fear of Mohammad, but when you set me free, I embraced Islam believing in the One and Only, the Almighty."
This is Prophet Mohammad (pbuh), a great man with great heart that never held any hate, anger, revenge or hard feelings toward a human being. The humanity will never taste the everlasting happiness without believing and following this unlettered Prophet, Mohammad Ibn Abdullah (pbuh)...You can bet on that.