What reward did Allah's Apostle (peace be upon him) say a judge would receive if their verdict was given according to the best of their knowledge and was either correct or wrong?
 Narrated `Amr bin Al-`As:                     That he heard Allah's Apostle saying, "If a judge gives a verdict according to the best of his knowledge and his verdict is correct (i.e. agrees with Allah and His Apostle's verdict) he will receive a double reward, and if he gives a verdict according to the best of his knowledge and his verdict is wrong, (i.e. against that of Allah and His Apostle) even then he will get a reward ."