Most Christians have got the concept of the Gospel as the means of entering the Christian life, but thereafter are unsure how to grow in the Gospel by steadily applying it to their lives. The result can be schizophrenic Christians who understand that they got saved by the Gospel of grace, but thereafter try and live saved through their own efforts.
Effort is important, but is in vain if not rooted in the life-changing truth and supernatural power of the Gospel. Paul says that we initially receive the Gospel and thereafter we need to take our ‘stand’ on the Gospel, hold firmly to it, and become established in it. We gradually grow into the Gospel of grace.