Positively show them during weekly bible reading, daily text how they have to better prepare to defend the truth. like : how do you explain the overlapping generation when you are at the doors? work to make them sharper, more knowledgeable witnesses.
Recent text was about Moses with the wisdom of the Egyptians. Clever people those Nile Dwellers, being able to build the Pyramids, while water lapped at the peak of Mount Everest. prepare to defend your faith!