What reason does Martin Luther King give for being happy he didn't sneeze after he was stabbed?

The doctors had told him that any minor movements including a sneeze could be the death of him as the blade was still inside him. He was happy he didn't sneeze as it would have costed him his life at that moment.

Dr. King could not immediately remove the blade; it was too close to his heart. He was told not to move an inch, not to speak. He was rushed to Harlem Hospital for emergency surgery.

The doctors later told him that any sudden movement - so much as a sneeze - could have cost him his life.