I heard Jeff Walling use this illustration when I was in college and it’s stuck with me ever since…
When I was a kid Mom would ask me to take out the garbage or she would “wear me out.” So I did. My motivation was fear. When I became a teenager Mom could no longer scare me with punishment so she offered something different. If would take out the garbage she would “give me $5 dollars.” So I did. My motivation was the reward. Now that I’m an adult I’m not fearful of Mom’s punishment nor that interested in her reward. But when she asks me to take out the garbage, I still do it. Why? Because I love her. I’m willing to do what she asks not because of what it gains me (safety or reward) but because of what it means to her. It’s a way for me to express my love to her and thank her for everything she’s done for me.
Something similar happens with God as we mature in our relationship with Him. Our initial motivation for obedience may have to do with fear. “I obey because I don’t want to go to hell.” But as we grow in that relationship we stop focusing so much on the punishment and start looking to the reward. “I obey because I want to go to heaven.” But as that relationship continues to mature so does our motivation for obedience. Eventually it’s not about the fear or the reward, but about the love. “I obey because I love Him.” Thus obedience becomes
something not just for my benefit, but His. It’s a way for me to express my love to God and thank him for everything he’s done for me. Obedience motivated by love is a beautiful thing.