He had studied Jewish law with one of the most famous teachers of his day. He had received authority from the Jewish high priest.
فَقَدْ دَرَسَ ٱلشَّرِيعَةَ ٱلْيَهُودِيَّةَ عِنْدَ قَدَمَيْ أَحَدِ أَهَمِّ ٱلْمُعَلِّمِينَ فِي أَيَّامِهِ .‏