1) Sin is crouching at our door: The word “crouch” reminds me of a cat getting ready to pounce on its prey. The situation is ominous.
2) Sin desires to have us: Once the cat leaps for its quarry, there’s little doubt over the outcome. Sin is crouching for us; it is getting ready to leap and destroy us. There’s little we can do — or is there?
3) We must master it: Sin is much easier to master beforehand rather than in the midst of it. When it is crouching, the potential for sin is there, but it’s not actual sin; it’s temptation. We know what to do with temptation and the devil who promotes it; we are to resist.