We overcome by two actions and one attitude. The two actions; 1) Jesus shed blood 2) Our testimony.
The one attitude is 1) Being willing to die for Christ's sake.
We are saved by Grace Through Faith → in the deity of Christ Jesus → in His virgin birth → in His sinless life → in His bearing our sins and diseases on the cross → in His death on the cross → in His resurrection from the dead → in His appearance to hundreds of people after His death → in His ascension → in His promised return → in the gift of His HolySpirit
Where there is a lack of faith in any of these tenets there is a lack of saving Grace because of unbelief.