In a famous sermon,the second caliph 'Umar banned mutah after the death of the Prophet (PBUH) with the following words:
"Two mutah were practiced during the time of the Prophet [i.e. temporary marriage and mutat al-hajj],but I forbid both of them and will punish anyone who practices either."(tafsir al-Razi,volume2,page167)
You can see that in al-islam .
According to this evidence, what was Umar's reason for banning Mutah? (Shia view)