Eucharist
Matthew 26:26-28
Take ye, and eat. This is my body... Drink ye all of this. For this is my blood of the new testament, which shall be shed for many unto remission of sins.
Context of the passage
At the Last Supper, Jesus institutes the Eucharist during the Passover meal, transforming the Passover into the New Covenant sacrifice.
Catholic reading
Jesus does not say 'this represents' but 'this is,' identifying the bread and wine directly with his body and blood, the institution narrative that grounds the Mass.
Common objection
Some say Jesus often used figurative 'is' statements, like 'I am the door.'
Response
Aramaic lacked a verb for 'represents,' but the sacrificial context ('poured out for many,' echoing Exodus 24) and Paul's warning about unworthy reception (1 Cor 11:27) show the Church understood this literally from the start.