" Jesus called his disciples to be both “salt and light.” Each image depicts a perfect balance between difference and yet involvement. Salt only helps the meat if it is chemically different from the meat, yet is spread out into it. Light only pushes back the dark if it is both different from the dark, yet perceptible instead of being hidden under a basket (Matthew 5:15). So the Christian church must both keep its distinctiveness—not assimilating to the non-believing culture—and it MUST stay engaged and involved in that culture, rather than separated from it. We must remain in relationships and conversations with non-Christian people and secularized institutions and fields—not treating them simply as opponents. We must do so even when it costs us. "

― Kathy Keller