People dont recognize that there are really two thieves of the Gospel as is discussed in scripture. One is the irreligious thief that does not understand his deep need for Christ and Gods mercy and grace. The other is the religious, moralistic thief that is trying to be good enough for God or trying to perform their way into heaven.
Lets read Tim Kellers words on the topic.
The two “thieves” of the gospel. Since Paul uses a metaphor for being “in line” with the gospel, we can consider that gospel renewal occurs when we keep from walking “off-line” either to the right or to the left. The key for thinking out the implications of the gospel is to consider the gospel a “third” way between two mistaken opposites. However, before we start we must realize that the gospel is not a halfway compromise between the two poles–it does not produce “something in the middle”, but something different from both.
The gospel critiques both religion and irreligion (Matt.21:31; 22:10). Tertullian said, “Just as Christ was crucified between two thieves, so this doctrine of justification is ever crucified between two opposite errors.” Tertullian meant that there were two basic false ways of thinking, each of which “steals” the power and the distinctiveness of the gospel from us by pulling us “off the gospel line” to one side or the other. These two
errors are very powerful, because they represent the natural tendency of the human heart and mind. (The gospel is “revealed” by God (Rom.1:17)–the unaided human mind cannot conceive it.)
These “thieves” can be called moralism or legalism on the one hand, and hedonism or relativism on the other hand. Another way to put it is: the gospel opposes both religion and irreligion. On the one hand, “moralism/religion” stresses truth without grace, for it says that we must obey the truth in order to be saved. On the other hand, “relativists/irreligion” stresses grace without truth, for they say that we are all accepted by God (if there is a God) and we have to decide what is true for us.
But “truth” without grace is not really truth, and “grace” without truth is not really grace. Jesus was “full of grace and truth”. Any religion or philosophy of life that deemphasizes or lose one or the other of these truths, falls into legalism or into license and either way, the joy and power and “release” of the gospel is stolen by one thief or the other.
“I am more sinful and flawed than I ever dared believe” (vs. antinomianism)
“I am more accepted and loved than I ever dared hope” (vs. legalism)
This is an important topic to me. Why? Because, both of these thiefs steal away something important to us. They steal the power of intimacy with God and with those we love around us. Without the centrality of the Gospel mindset, we will feel the need to portray some level of worthiness around other people to feel good about ourselves.
To achieve a deep intimacy with God and those around us the Gospel being centric to our thinkology is absolutely essential.