Then came the day of unleavened bread, when the passover must be killed. The passover - Πασχα, Luke 22:1, is the name of the festival; το πασχα here is supposed to be the name of that on which they feasted, viz. the sacrificed paschal lamb. But see the notes on Matthew 26 (note), and especially the observations at the end of that chapter, (Matthew 26:75 (note)).
Related Commentaries of Luke 22:7
Luke 22:7
7 Then came the day of unleavened bread, when the passover must be killed.