Those who aspire to play guitar, know that the learning process means enduring sore fingers and raw skin, but after enough practice, callouses form—making the pain fade and the music flow. Yet, those same callouses that strengthen a guitarist’s skill can eventually dull sensitivity to touch and feeling. In life, there’s a similar risk: we work hard to build spiritual resilience, but sometimes what makes us tough can make us insensitive, less tender to others and even to God. Jesus addressed this danger in Revelation 2:1-7, which contains his words of encouragement, correction, and promise for callous Christians.