Why could Paul completely discard his old way of life under the law?
Because he saw the truth of the Gospel of Christ—that He died, shed His blood, and rose from the dead—Paul could discard his old life under the law. The law’s ordinances were against us and contrary to us; Christ blotted them out, took them out of the way, and nailed them to His cross (Colossians 2:14).
Les explains that once Paul saw the truth of the power of the Gospel of Christ—how He died, shed His blood, and rose from the dead—he could literally destroy everything of the old account. In Colossians 2:14, the work of the cross blotted out the handwriting of ordinances that was against us, which was the law, especially the law practiced at Christ’s time, a compilation of 613 rules and regulations. That law was absolutely contrary to human nature. All these things contrary to us, He took out of the way and nailed to His cross. Paul then helped believing Jews like himself see that the old economy had been totally done away with, nailed to His cross. Paul reasoned that if he returned and told converts he was wrong and had to put them back under the law, he would be building again that which he had destroyed.