Frankly, none of us are going to make the cut to follow Jesus. Our desires for soft pillows and comfortable beds, for fulfilling family and social obligations, will frequently have higher priorities than following Jesus — especially following Jesus all the way to the cross. We might be willing to give up some evils in our lives to follow Jesus, but to give up all these good things — to put them as a lower priority than Jesus? That is radical discipleship, but Paul writes about doing this in Phil 3:4-11. He considers all his past, good, religious deeds as “rubbish”.

Perhaps the image of putting one’s hand to the plow and not looking back (or driving forward in a car while not looking out the back window) refers to looking back both at all the very good things in our lives (and in a congregation’s life), like family and friends, comforts and satisfactions, “successful” programs; but also all the sins in our lives, which have been forgiven by Christ. We can neither wallow in our past sins nor boast of our past successes if we are to be fit for the kingdom of God.

Brian Stoffregen, Exegetical Notes