"You yourselves also know, Philippians, that at the first preaching of the gospel, after I left Macedonia, no church shared with me in the matter of giving and receiving but you alone.  for even in Thessalonica you sent a gift more than once for my needs."

What does it mean to be a church that shares?

Paul is reminding the Philippian church that there was a time, earlier in Paul's ministry, that they were the only ones who would give to the cause of missionary work.  Why is that significant?

Paul saw something great happen in the church at Philippi:  He saw a people reach out and give to a cause that was not their own.  He saw a church with concern for others, not just themselves.

This is what every church is called to do, but few take up the call.

Paul takes this time to encourage them to continue to have this mindset.  Think of others before yourselves.