The problem with a divided, unfocused mind is that it is, as we would say today, all over the place, seeking fulfillment in a host of things, pursuing a wide variety of goals, but rarely, if ever, coming to grips with the pursuit of revealed truth.
Many of us have television to thank for having a mind like this as it has played a major role in destroying peoples' attention span. The attention span of Americans is now getting down into the neighborhood of seven minutes: the length of time between advertising on television. We have a hard time focusing for any period of time, and television is constantly pushing its mind-numbing banalities into our minds, making it difficult for us to do what is absolutely necessary for us to do, that is, to spend time in heartfelt prayer and study, seeking God. The chances are very great that we sit down to read the Bible, and our eyes get heavy, and we struggle to fight off sleep. It happens because we have no passion for Jesus Christ.
God is teaching us what defragments our mind: seeking Him with a passionate desire to be like Him. This works to make our minds one with His.