Zeal of the convert

The zeal of the convert is a term describing the very fervent devotion to new beliefs, which are completely different from one's old beliefs. For example, Paul the Apostle, formally known as Saul of Tarsus was a Jewish Pharisees who persecuted Christians until he had a life changing vision on the road to Damascus and became a Christian missionary who spent his life spreading Christianity throughout the Roman empire and was later executed in Rome for his devout Christian beliefs.

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