It means that - If you hold or keep your peace, you do not speak, even though there is something you want or ought to say.
Explanation:
However according to the bible “Peace I leave with you; my peace I give to you. Not as the world gives do I give to you. Let not your hearts be troubled, neither let them be afraid.” “Therefore, since we have been justified by faith, we have peace with God through our Lord Jesus Christ.”
B. The first paragraph discusses the idea that Americans are united as one despite their differences. The second paragraph discusses the idea that acts of intolerance make it difficult to believe that Americans are united as one.