18 But the Church ceases not to kiss the feet of Christ, and therefore in the Song of Songs she desires not one but many kisses, and like Holy Mary she is intent upon all His sayings, and receives all His words when the Gospel or the Prophets are read, and “keeps all His sayings in her heart.” So, then, the Church alone has kisses as a bride, for a kiss is as it were a pledge of espousals and the prerogative of wedlock. Whence should the Jew have kisses, who believes not in the Bridegroom? Whence should the Jew have kisses, who knows not that the Bridegroom has come?
Source: Letters (New Advent)