What is Sin?
Sin is the natural tendency to exclude God from your decision making process and to trust in and rely on yourself for success in life!
Therefore the key factor in eradicating Sin from your life is the breaking and submitting of your will to God! That's what you do when you receive Jesus as your Savior, in a very specific way yet with a very broad application, you surrender your will to God and make a quality decision to trust Him day by day for the rest of your life. He in turn grants you the ability to do this by changing your inner nature from one of inherent rebellion to one of submissiveness and obedience.
Now, when Jesus died on the cross, His blood was used as a sacrificial offering to God, paying for your deliverance from Sin's power and purchasing your freedom from the devil. In other words, He used His blood to redeem you or buy back your freedom, thus liberating you from the control of the devil and giving God ownership and control of your life once more.
You must understand since God laid down the law in the Garden of Eden, which said 'If you sin you must die', that law has always and will always be in effect. This means whenever you sin you owe God your life, plain and simple!
This is exactly why Jesus died; He gave His life in place of yours!
Now, how was that transaction ratified? How did He prove to The Father that He really did die in your place? He offered His blood to The Father in Heaven! Remember the life is in the blood!
"Neither by the blood of goats and calves, but by his own blood he entered in once into the holy place, having obtained eternal redemption for us. For Christ is not entered into the holy places made with hands, which are the figures of the true; but into heaven itself, now to appear in the presence of God for us." (Heb 9:12 & 24)
Just as the High Priest in the Old Testament offered a spotless Lamb's blood to God to pay for the sins of the people, so Jesus offered His spotless blood to God to pay for your sins and the sins of the entire world.
So, by offering His blood He was offering His life - His life for yours!
When this transaction took place he broke the power of Satan and sin from off your life by redeeming you from the control of the devil.
Now, because of this you are no longer a slave to the sinful passions and appetites of your body, but have absolute authority over them. You have authority because it is through the offering of Jesus' blood you have the nature of God in you and that divine nature gives you mastery over Satan! Jesus said, "Behold, I give unto you power (authority)... over all the power (ability) of the enemy," (Lu 10:19)
You can overcome because you realize you have authority over the devil's ability to deceive you. He can no longer influence and manipulate you into sinning against God, unless YOU allow him to!
You are the master of sin... You are not its slave anymore! All because of the blood that set you free from its control when it was used to pay for your nature change! This is what it means to overcome by the blood!
It is appropriating the efficacy of that blood by faith. It is you understanding that the shedding and offering of that blood is the basis of your freedom from the authority of Sin and Satan and using this knowledge and understanding to stand against the Enemy and defeat him in every contest!
It is you boldly declaring to the devil, "Satan, I plead the power in the blood of Jesus Christ against you and deny you the right to rule over my health, my wealth or my attitude! Now, get thee hence!!!
This... is overcoming by the blood of Jesus!
It is you declaring, "Devil, I am washed in the blood of Jesus! I will NOT give in your temptation to sin and deny the Lord who bought me. I bind you in the Name of Jesus! Now, Go!!!