Occasionally I see reports of happenings that cannot be humanly explained–of visitors unexpectedly appearing to assist in times of crisis, or warning of impending danger. These can only be explained as the intervention of God’s angels. In the Bible, angels occasionally assumed visible form–at the birth of Jesus, for example. But usually angels go about their business unseen and unrecognized. They never draw attention to themselves, but point us instead to Christ.
–Billy Graham, Hope for Each Day