Faithful in Colossae

I'm working my way through Colossians (translation and commentary) and I'm convinced that a number of the references to pistis should be translated as "faithfulness" rather than "faith". Consider the following:

1. Pistos as "faithful"

• Colossians 1:2 - To the holy and faithful brothers in Christ at Colossae: Grace to you and peace from God our Father.
• Colossians 4:7, 9 - Tychicus will tell you all about my activities. He is a beloved brother and faithful minister and fellow servant1 in the Lord ... and with him Onesimus, our faithful and beloved brother, who is one of you. They will tell you of everything that has taken place here.
• Colossians 1:7 - just as you learned it from Epaphras our beloved fellow servant. He is a faithful minister of Christ on your behalf.

This is the standard adjectival use of pistos, but it is prominent in describing members of the Pauline circle. The Colossians are also lauded as "faithful" and I wonder if much of Paul's instruction is going to hedge up this point in light of the Colossian "philosophy".

2. Pistis as "faithful"

• Colossians 1:4-5 - since we heard of your faithfulness in Christ Jesus and of the love that you have for all the saints, because of the hope laid up for you in heaven. Of this you have heard before in the word of the truth, the gospel. This could be "faith" but the surrounding description clearly sees the faith as something that is or becomes displayed in action, i.e. in love.
• Colossians 1:23 - if indeed you continue in faithfulness, stable and steadfast, not shifting from the hope of the gospel that you heard, which has been proclaimed in all creation under heaven, and of which I, Paul, became a minister. Again "faith" does make sense here, but the surrounding description sounds far more like "faithfulness".
• Colossians 2:5-7 - For though I am absent in body, yet I am with you in spirit, rejoicing to see your good order and the firmness of your faithfulness in Christ. Same as above, "faith" could work, but "faithfulness" seems supported by the context.

3. Pistis as "faith" or "believing"

• Colossians 2:7 - rooted and built up in him and established in the faith, just as you were taught, abounding in thanksgiving.
• Colossians 2:12 - having been buried with him in baptism, in which you were also raised with him through faith in the powerful working of God, who raised him from the dead.

These seem to be clearer expositions of faith as the act of believing (2.12) or that which is believed (2.7).

What does this mean: Colossians is not simply about right doctrinal belief, but about a life lived in faithfulness to the Lord under adverse circumstances. It is also about ministers of the gospel remaining faithful to their calling. It evidently does include a reference to believing and that which is believed, even if that does not become the primary focus.