Ben Ellis, who is fighting an aggressive form of cancer, looked out the window of his home and saw his school's students singing to him in support.
Ellis taught Latin and Bible studies at Christ Presbyterian Academy in Nashville, Tennessee. He recently had to stop teaching while undergoing chemotherapy and radiation.
In an amazing outpouring of support, the entire student body from his school, over 400 students, came to his house and sang to him.
The video was posted online by country superstar Tim McGraw, who said he was tipped off by a friend who wanted to share the act of kindness.
In just 2 days, the video has nearly 20 million views on Facebook.