"By the which will we are sanctified through the offering of the body of Jesus Christ once for all".
Let's repeat.
ALL.
If the Christ you serve didn't die for ALL of your sins, if His sacrifice just wasn't quite perfect enough, what's the point in worshiping Him?
Thankfully, Christ did in fact die for all our sins, so skip the non-Scriptural Purgatory and simply revel in the amazing grace offered by Christ who died for ALL.
Yes, the one sacrifice of Jesus on the Cross won us our salvation. In this we all agree. But notice that by this we are sanctified, i.e. made holy, not just justified. Is there any sinfulness, any selfishness, still lurking in your soul? If so, then this process of sanctification won by the price of the Cross is not yet complete.
Amen!