The resurrection is not an additional achievement to the work of Christ, it is an elemental transaction that happened, the climactic conclusion to the redemptive work that sealed our justification. Not only did he take our sins upon the cross, but he absolved our guilt in his resurrection. We are redeemed because Jesus defeated death.
Whenever we compromise the Gospel, it is because we are ashamed of it, because we do not know its power. The value and power we see in this Gospel that saves, is directly reflected by how clearly we understand what we are saved from.