In this quote, David Herbert Lawrence is recommending that the constant promo of peace can really have the opposite impact and make war seem more likely. He is highlighting the paradox of how the loud and persistent messages of peace can produce a sense of stress and worry, rather than promoting harmony and tranquility. This could be due to the truth that continuously speaking about peace can advise individuals of the possibility of war, or it could be an outcome of the aggressive and strong nature of some peace propaganda. Overall, Lawrence is cautioning versus the possible unfavorable consequences of extremely enthusiastic peace promotion.
"When the principles that run against your deepest convictions begin to win the day, then the battle is your calling, and peace has become sin. You must at the price of dearest peace lay your convictions bare before friend and enemy with all the fire of your faith"