Yesterday, I was pointing out that “peace” in the Bible has a broader range of meanings than merely the absence of conflict. This is especially true in Hebrew. We have to feel that the Hebrew meaning influenced the New Testament writers; this is especially true in the gospel sayings, since Jesus spoke Aramaic, not Greek.
So think about some of the parallel ideas with the word peace:

Fulfillment
Wholeness
Prosperity
Well-being

If we are peacemakers, we are actively working to create these things. We can see some of this in Jeremiah’s words for the exiles in Babylon:

“Build houses and live in them; plant gardens and eat their produce. Take wives and have sons and daughters; take wives for your sons, and give your daughters in marriage, that they may bear sons and daughters; multiply there, and do not decrease. But seek the welfare of the city where I have sent you into exile, and pray to the LORD on its behalf, for in its welfare you will find your welfare.” (Jeremiah 29:5–7)

The word which the ESV translates as “welfare” is the word “shalom” — peace. The NIV inserts the word prosperity (“seek the peace and prosperity”), trying to convey the idea that peace is much more than absence of war.

As exiles, as strangers and aliens, we live here in Babylonia seeking to be shalom builders, seeking to create good and not ill, seeking to build and not destroy, working for all that is life and opposing all that is death.

As Rex pointed out in a comment yesterday, that’s a far cry from a passive lifestyle. Yet it’s a life of waging peace