Faisal al-Duwaisan, from the Shia minority group in parliament, decided to resign after Hamdan al-Azemi, from the Sunni majority, made derogatory remarks about his faith.
"I was deeply hurt... by the contempt and insult against my religious sect by my colleague,” Duwaisan stated in his resignation note. He said during a debate on Tuesday Azemi had told him that he should rectify his sect, triggering a confrontation between Azemi and several other Shia lawmakers.
At the end of the parliamentary session, one of the Shia lawmakers, Abdullah al-Tameemi, and Azemi briefly quarreled before other lawmakers restrained them.
Duwaisan said he will not take back his resignation unless he either receives an apology from Azemi for the insult against his sect, or disciplinary action against Azemi is taken by the parliament.
Duwaisan is a follower of Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei. He was originally a Sunni who later converted to the Shia sect.
Kuwait has fifty lawmakers in parliament. Seven of them are Shia MPs.
In 2013, Kuwait passed a national unity bill to forge stronger bonds between its 1.3 million native population consisting of both Shias and Sunnis. The law prescribes several years in jail for anyone committing illegal acts related to ethnic or religious hatred.