Any relationship, whether with a spouse, child, friend, or fellow crew member requires some form of self-discipline to keep healthy. It is no different with the most important relationship in our lives.
How often do we choose to avoid the required disciplines to know, love, and obey the One who made us and died for us? How much different are we sometimes from the person who openly rejects Christ? Perhaps more than we would like to think.
The human heart, even the redeemed human heart, is capable of amazing feats of rationalization. We employ such mental gymnastics to justify putting God on a shelf in our lives.
To put Him there is to sin grievously against a Savior who loves us more deeply than any other person in our lives, and who deserves our steadfast love in return.
Behold, I stand at the door and knock. If anyone hears my voice and opens the door, I will come in to him and eat with him, and he with me. Revelation 3:20 (ESV)