"Holy Thursday is the first day of the Easter Triduum, the most sacred days of the Catholic faith. It begins with the Mass of the Lord’s Supper, commemorating the Last Supper celebrated by Jesus and his disciples on the Jewish holiday of Passover. It’s not a Holy Day of Obligation, but many Catholics attend Mass. During this Mass, the priest washes the feet of some members of the parish in memory of Jesus washing the feet of his disciples.
But perhaps the most significant thing that happened on Holy Thursday was that Jesus instituted the Sacrament of the Eucharist."
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