And so where do you see the Holy Spirit saying Paul suffered all the consequences of sin and we are saved through his merits? Even if said in a certain technical way, a recurrent problem in Mariology is that it expects the laity to understand such, thus the language of Scripture is reticent in praise of men and very sober in its assessment of them, while exalting God repeatedly and as unique. Thus even the Trinity is not explicitly spelled out.
Colossians 1:24.
We are IN Christ. We are Baptized INTO Christ. THe distinction between His merits and those of the perfected is there, but tenuous.