Responsorial Psalm (Ps 118)
R. Give thanks to the LORD, for he is good, his love is everlasting.
The stone which the builders rejected has become the cornerstone.
By the LORD has this been done; it is wonderful in our eyes.
This is the day the LORD has made; let us be glad and rejoice in it.
R. Give thanks to the LORD, for he is good, his love is everlasting.
https://bible.usccb.org/bible/readings/040724.cfm
As the Psalm points out, God’s mercy endures forever. This is the Octave Day of Easter, and even though the Easter Season will continue for 50 days all the way to Pentecost Sunday this Sunday focuses on Divine Mercy which gives even doubting disciples a second chance.