Years ago, an elderly friend asked if I knew another man who studied at the Harvard Business School named Stephen R. Covey. I replied that I knew of him though his “Seven Habits,” of course, but had not personally met him. My friend said, “Let me tell you a story about that man, which tells you everything you need to know about him:

“I was a freshman at Harvard College in 1956. I went to our Mormon church on my first Sunday there; and before I could sit down, young Covey, who himself had just arrived a few weeks earlier to begin his studies in the Harvard MBA program, approached me and asked if I could help him that afternoon at a meeting in downtown Boston.

“I agreed, and we met at the entrance to the Red Line station in Harvard Square that afternoon. Covey had a heavy bag and a wood box.

When I asked of their purpose, he replied, ‘We are going to find a busy walkway through Boston Common. I’m going to stand on this box and give a sermon on the life of Jesus Christ. Your job is to invite as many people as possible to stand there, to hear my sermon. Then you need to look at their faces, and if they seem interested, give them one of the pamphlets in this bag.’ I did what I was told. Steve delivered a wonderful sermon to a group of about 50 people.”

My elderly friend concluded, “That event changed my life. He became my idol. While most of his classmates at the time were resting with a beer from their demanding program, Stephen Covey was busy at a higher work.”

Stephen Covey changed my life, too, as I have gotten to know him well. What he wrote is who he is. Whenever I walk through Boston Common, I imagine Stephen Covey in his early 20s, standing on a wooden box with a clear voice, with the message about his Redeemer who was his Beacon. Stephen was proactive. He began his career with its end in mind. And he put first things first.

I am grateful for this man, but I will not miss him. He will continue to be with me every day, through the things that he taught me to do.

Clayton Christensen is a professor at Harvard Business School and the author several books, including The Innovator’s Dilemma and, most recently, How Will You Measure Your Life?

Read more:

A tribute to Stephen Covey, from one leadership sage to another

The best new leadership books

PHOTOS | Athletes on what motivates their best performance

Like On Leadership? Follow us on Facebook and Twitter:

On Leadership: @post_lead | Editor: @lily_cunningham