Fight to the Death & the City Is Your Own

I have just begun reading The Christian in Complete Armor by William Gurnall. The whole book is a call to arm yourself in the battle that is the Christian life. I've only read the first 18 pages, but I can already feel God using the words of Mr. Gurnall to revive the Christian soldier within. Here is one passage that has affected as of late.

As part of Christ's army, you march in the ranks of gallant spirits. Every one of your fellow soldiers is the child of a King. Some, like you, are in the midst of the battle, besieged on every side by affliction and temptation. Others, after many assaults, repulses, and rallyings of their faith, are already standing upon the wall of heaven as conquerors. From there they look down and urge you, their comrades on earth, to march up the hill after them. This is their cry: 'Fight to the death and the City is your own, as now it is ours! For the waging of a few days' conflict, you will be rewarded with heaven's glory. One moment of this celestial joy will dry up all your tears, heal all your wounds, and erase the sharpness of the fight with the joy of your permanent victory.'