Hazrat Khalid bin Waleed-----

• When he besieged the fort of the Christians during the war, their oldest priest came to you. There was poison in his hand. He asked Hazrat Khalid bin Waleed:
  "You lift the siege of our fort. If you conquer our other forts, we will give you the possession of this fort without a fight."
  Hazrat Khalid said:
  "No... we will conquer this fort first and then move on to another fort"
  "If you do not raise the siege of the fort, I will commit suicide by consuming this poison." My blood will be on your neck"
  "It is impossible for you not to die and die."
  "If you believe this, then take this poison."
  You grabbed the poison and prayed:

Then you spit out the poison and drank the water from above. The old priest was completely sure that Ah would reach the valley of death in a few moments, but he was surprised to see that within a few minutes, sweat broke out on his body. Nothing else happened. Hazrat Khalid bin Waleed addressed the priest and said:

The priest ran away without giving any answer and went into the fort and said:
"O my people... I have come together with such a nation, by God Almighty, that does not want to die." They only know how to kill. As much poison as one of their men ate, if we mixed it with water and ate it, all the people of the fort would have surely died, but when this man died, he did not even faint. If you believe me, hand over the fort to him and do not fight with them.”

Therefore, the fort was conquered without a fight, only by the faith of Hazrat Khalid bin Waleed---------
History of Ibn Asakir