Salvation
Galatians 5:6
For in Christ Jesus neither circumcision availeth any thing, nor uncircumcision; but faith that worketh by charity.
Context of the passage
Paul writes to the Galatians, who were tempted to think circumcision and the Mosaic law were necessary for salvation apart from Christ.
Catholic reading
Paul defines the faith that truly matters as 'faith that worketh by charity,' precisely the Catholic understanding that saving faith is never sterile but is inherently active in love, distinguishing it from a bare intellectual assent.
Common objection
'Worketh by charity' simply describes what faith naturally produces as evidence, without charity being part of what justifies.
Response
Paul's Greek construction (pistis di' agapes energoumene) describes faith as actively operating through love as a unified reality, not as two separate items where one merely follows the other, showing love is intrinsic to the very faith that avails before God.