Shouldn't the RCIA explain the risk of mortal sin?

In RCIA last night a team member brought up the point that somewhere in the Bible it refers to “all sin being equally bad and seperating us from God”. I tried to point out 1 John 5:16-17 about Mortal Sin, but didn’t get through.
What Scripture Reference was he using (as I have heard that before but don’t know where it it) and shouldn’t we be explaining to Candidates and Catechumans that mortal sin puts us at risk from being eternally seperated from God?
Thank you in advance.
God Bless your apostolate.

Dear C,

This question you should ask the team member. Ask HIM what Scripture reference he was using. The Catechism of the Catholic Church # 1854 states: “Sins are rightly evaluated according to their gravity…” Number 1855 distinguishes mortal and venial sins from each other.

Every member of the team as well as every member of the RCIA ought to have a copy of the Catechism. And they should read it!

Fr. Vincent Serpa, O.P.

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