If you can't find enough proof that the Church believes a sin is mortal, is it mortal?

[Ben_Sinner]

for an example. I’ve read that the early church fathers were completely against using musical instruments during worship, but they never really hint how serious the sin is to use or listen musical instruments outside the church. And the church today uses musical instruments…so if i decide to listen to music with instruments in it with full knowledge and deliberate consent but not really 100% sure if the matter is grave matter since none have them said “THIS IS A MORTAL SIN TO USE MUSICAL INSTRUMENTS”, is that considered a mortal sin?

 

[Fr.Vincent_Serpa]

Dear friend,

You are obliged to live by the CURRENT teachings of the Church. The current Catechism of the Catholic Church will provide you with all the proofs you need.

Fr. Vincent Serpa, O.P.