"Justified by Faith"?

Does your own faith save you?  Maybe we should ask, faith in what? And what kind of faith?

Note how T.F. Torrance explained Jesus’ faithfulness:

Jesus Christ stood in our place, taking our cause upon him, also as Believer, as the Obedient One who was himself justified before God as his beloved Son in whom he was well pleased. He offered to God . . . a perfect faith and response which we are unable to offer, and he appropriated all God’s blessings which we are unable to appropriate. Through union with him we share in his faith, in his obedience, in his trust and appropriation of the Father’s blessing; we share in his justification before God. Therefore when we are justified by faith, this does not mean that it is our faith that justifies us, far from it—It is the faith of Christ alone that justifies us, but we in faith flee from our own acts even of repentance, confession, trust and response, and take refuge in the obedience and faithfulness of Christ—“Lord I believe, help thou mine unbelief.” That is what it means to be justified by faith. (“Justification: Its Radical Nature and Place in Reformed Doctrine and Life,” Scottish Journal of Theology, vol 13, no 3. pp. 225-246.)

As Joseph Tkach explains in this article, our faith is both active and passive. We trust in Christ, and we trust in Jesus' perfect faith on our behalf, not on our own imperfect (and sometimes missing!) faith.