The possibility of legalising same-sex marriage arose from an initiative by the centre-right Kyriakos Mitsotakis. A noteworthy detail is that the law had to be passed with the support of the left, despite Mitsotakis' party having a majority in parliament. A significant portion of his own party voted against it. 

These opposing votes can be largely explained by the resistance of the Orthodox Church in the country. Church leaders had called for demonstrations against the law, citing "concerns" about the position of families consisting of a father and a mother. The Holy Synod of the Greek Orthodox Church also sent letters to members of parliament. One of the arguments against introducing equal marriage rights that the Church put forward was the declining birth rate in Europe. 

Currently, marriage for same-sex couples is legal in 36 countries worldwide. Greece becomes the sixteenth country in the European Union to recognise equal marriage rights. However, the rights are not entirely equal. Surrogacy is only legal for heterosexual couples experiencing difficulties conceiving a child. 

Since 2015, Greek same-sex couples have been able to enter into a civil partnership. Even then, the Orthodox Church opposed the measure.