The most impressive thing about “A Common Word Between Us and You,” an open letter to the world’s Christian leaders signed by 138 Muslim scholars, is that it exists. (See news report.) The second most impressive thing is the economy of its argument. The scholars resist the innate desire to touch on everything pertinent to Christian-Muslim dialogue and instead invite Christians to remember Jesus’ words about loving God and neighbor. They argue that the twin commandments to love God and to love neighbor provide a clear basis for interfaith peace and understanding.