A college professor always brought a tennis ball to class. He set it on the podium but never said what it was for. One day, a student fell asleep, and the professor took the ball, threw it, and hit the student on the forehead to wake him up. The next day he walked in, took out a baseball, and put it on the podium. Seeing the baseball, everybody stayed alert in his class. Before Jesus left the earth, He told His disciples that people must stay alert for His return to earth. We learn from Mark 13 several ways we can stay alert while He’s away. He said we should not be misled by false teachers that claim to know when He will return. He said such false teachers often design their messages to gain followers. He said we should stand firm in our witness for Him, even though we may be demonized and persecuted. He said we should remain faithful and loyal to him even though others may urge us to abandon His teachings. Jesus then said, no one knows the day or hour when He will return, not even the angels in heaven or the Son Himself. He said only the Father knows. And since we don’t know when that will be, we should be on guard! Stay alert! How do we do that? We love God passionately; we live each day to please Him; we share the message that God forgives those who trust His Son; we work to foster justice and morality in our world.