punishment that destroyed men and horses, and it withdrew, humbled and exhausted. Allah fulfilled His promise and granted victory to His servant. The enemy now suffers grievous affliction, crushing reversals, and tribulation that has encompassed it. Islam, meanwhile, continues to grow in might and enjoy blessing upon blessing, for the Prophet, may Allah bless him and grant him peace, said:

“At the turn of every century, Allah sends this community someone who renews its religion for it.”

This religion continues to advance and undergo renewal. I sincerely counsel the king and his companions—by Allah, besides whom there is no god, who sent down the Torah, the Gospel, and the Criterion.

The king knows that when the delegation from Najrān—all of them Christians, including the bishop and others—came to the Prophet, may Allah bless him and grant him peace, he called them to Allah, His Messenger, and Islam. They spoke to him about the Messiah and debated with him. When the proof against them had been established, they began to evade it. Allah therefore commanded His Prophet to invite them to a mutual invocation of curses, as He said:

“Whoever disputes with you concerning him after the knowledge that has come to you, say: ‘Come, let us call our sons and your sons, our women and your women, ourselves and yourselves; then let us pray earnestly and invoke Allah’s curse upon the liars.’”

When the Prophet, may Allah bless him and grant him peace, proposed this, they consulted among themselves and said: “You know that he is a prophet, and that no one who has engaged in a mutual invocation of curses with a prophet has ever prospered.” They therefore paid him the jizya, entered the covenant of protection, and asked to be excused from the mutual invocation of curses.

Likewise, the Prophet, may Allah bless him and grant him peace, sent his letter to Caesar, who ruled the Christians in Syria and across the sea as far as Constantinople and elsewhere, and he was a king