How can Catholics say we believe "A" when it's only God ALONE who can do "A"?

“Love the Lord with all your heart, and with all your soul,

                                  and with all your MIND”--Matt 22:37

I am not able to articulate this week's Apologetics question in a simple, pithy format, but here's the gist:
 
How can Catholics say we believe  "A"  when it's only God ALONE who can do "A"?
This objection takes many forms:

• How can a priest forgive sins?  Only God can do that!
• How can Mary be co-redemptor?  Only Christ does that!
• How can a saint help us to find our lost car keys?  Only God can do that!
• How can the Catholic Church say that she gave us the Bible?  The Bible comes from God!
• How can the Catholic Church say it has authority?  God is my authority, not the Church!
  

I find these objections curious, in light of this Sunday's second reading from 1 Corinthians:

Although I am free in regard to all,
I have made myself a slave to all
so as to win over as many as possible.
To the weak I became weak, to win over the weak.
I have become all things to all, to save at least some.
All this I do for the sake of the gospel,
so that I too may have a share in it.

Here we see that St. Paul declares that he can save souls! Yep, folks, that's what he says.  He (Paul) saves souls!  And he repeats it elsewhere in the NT: 

To the weak I became weak, to win over the weak.
I have become all things to all, to save at least some.-1 Cor 9:22

And here Paul says that we can save ourselves!  

Attend to yourself and to your teaching; persevere in both tasks, for by doing so you will save both yourself and those who listen to you.--1 Timothy 4:16

I thought only Jesus saves??!!!??

Now, naturally, all Christians understand that St. Paul can only save souls through the authority of Christ and the power of God, working through St. Paul.

So if non-Catholic Christians can tolerate St. Paul saying that he saves souls, without Paul having to qualify the statement with, "Of course, we all know that when I say that I save souls it's only through the power God has given me"   we can see how the Church understands that each of those things we proclaim we can do is ONLY through the power of God and authority Christ has bestowed on us.

Thus,

• The priest forgives sins only through his cooperation with Christ's forgiveness of sins.
• Mary is co-redeemer (as we all are when we assist in the salvation of souls!) because she has aligned her will to God's.
• St. Anthony finds our car keys only because God has assisted him in this regard.
• The Church discerned what ancient Christian writings were inspired only under the guidance of the Holy Spirit.
• The Church has the authority to "bind and loose" only because she was given this authority by Christ.

It's just understood when we say those things that it's only through the authority God has given!

For more in-depth study visit these websites:

Catholics Come Home

Catholic Bible online

Catechism of the Catholic Church online

"Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect" - 1 Peter 3:15