We are but of yesterday, and we have filled every place among you – cities, islands, fortresses, towns, market-places, the very camp, tribes, companies, palace, senate, forum – we have left you nothing but the temples of your gods … if such multitudes were to break away from you, and betake themselves to some remote corner of the world, why, the very loss of so many citizens, whatever sort they were, would cover the empire with shame … you would be horror-struck at the solitude in which you would find yourselves, at such an all-prevailing silence, and the stupor as of a dead world.  You would have to seek subjects to govern.  You would have more enemies than citizens remaining.  For now it is the immense number of Christians which make your enemies so few – almost all the inhabitants of your various cities being followers of Christ. 

Tertullian (155-220)

…from an open letter to the Roman Senate

Outsiders will judge us not so much by what we say (for most will not listen to us anyway), as by what we are and what we do.  We know virtue by practice rather than through boasting … if not lived, it isn’t worth talking about.  We do not preach great things, we live them … Words are hollow unless they are lived.  We live our doctrine before we teach it.  Our lifestyle is what we truly believe.

Cyprian, (Bishop of Carthage in North Africa, 210-248)

The Church’s growth is the product not of our persuasive powers, but of our persuasive life. We must ask ourselves whether our lives open the door for Jesus, or whether they cause people of judge Him negatively… if our actions do not match our words, they turn from astonishment to blasphemy and dismiss Christianity as some kind of myth or error…

Origen of Alexandria (185-253)