Math theories often contain the shorthand phrase “if and only if,” sometimes abbreviated iff. This means that a given if-then statement is true both forward and backward. Another way to look at it is that the two “sides” of the if-and-only-if statement are equivalent – they mean the same thing.
Example: A polygon is a square if and only if it has four sides of equal length joined by four right angles. Both statements are true: 1. If a polygon is a square, then it has four sides of equal length joined by four right angles. 2. If a polygon has four sides of equal length joined by four right angles, then it is a square.
We say that such conditions – each “side” of the statement – are both necessary and sufficient.
Similarly, the sacrificial death of Christ is both necessary and sufficient for salvation.
Why was it necessary for salvation?
The Bible teaches us that every person has sinned. (Romans 3:23) No one is exempt from this, even if they are a Good Person. (Romans 3:10) And the penalty (or wages, as it is often stated) for sin is death. (Romans 6:23) In other words, we are all facing the death penalty. God is holy and perfect, and sin cannot be in His presence, just as darkness cannot exist around a light. We are spiritually separated from God.
We can’t do anything about this condition on our own. There’s no way for us to be good enough, smart enough, religious enough, or obedient enough to be pardoned from this death penalty. We can’t get rid of our own current sinfulness, and even if we could, we can’t go back in time and erase our past sins. Without the shedding of blood, there is no forgiveness of sin. (Hebrews 9:22)
Amazingly, God took the initiative on this. He prepared a way. In fact, He not only prepared a way, He became The Way.
In the Old Testament, we see temporary “fixes” for the problem. Sacrifices were accepted at certain times and in certain ways for certain sins. (Those deaths would, in effect, pay the wages or penalty of the sins.) Also, once a year, the high priest would approach God to atone for the sins of the people. But these sacrifices would have to be repeated. It was a bit like putting a band-aid on a cancer. They didn’t fix the problem. In fact, they were never intended to fix the problem. The purpose was to remind the people that there IS a problem and to point to the ultimate solution – Jesus.
Jesus came as the permanent solution to that problem. His death was necessary for salvation – being reconnected with God, having the sin penalty paid in full.
Why was His death sufficient for salvation?
It’s important to understand that Jesus had no sin of His own. He is God’s Son, born of the virgin, Mary. He was/is fully God. He was/is fully human. This is critically important because if He had sinned, then He would be under that same death penalty, and the crucifixion would have simply been the just penalty for His sins. It would have accomplished nothing for anyone else.
Instead, He – who had no sin of His own – didn’t simply take on our sins, He BECAME sin on our behalf. (2 Corinthians 5:21) He became my lies, my pride, my rebellion, my greediness, my gluttony, my selfishness, my anger, my hypocrisy. And then all of that sin was put to death. Once and for all. The penalty was paid. There’s no need for any other sacrifice. It never has to be repeated. As the old hymn says, “Jesus paid it all. All to Him I owe. Sin had left a crimson stain. He washed it white as snow.”
Jesus’ death on the cross was sufficient for my salvation and yours.
So, if His death was both necessary and sufficient for salvation, does that mean that every person is automatically saved as a result? No. This salvation is offered as a gift, and like all gifts, it must be received to be of any value to you. Someone might buy the Hope diamond for you for Christmas, but you won’t be any wealthier if you never accept that gift.
How is this gift of salvation received? Again, it goes back to necessary and sufficient. You must acknowledge that His death was necessary for your own sin. And then you must believe that His death was sufficient for your salvation. In other words, you believe that He is the way – the only way – to be reconnected to God and forgiven of your sin, and you trust that His death fully satisfied the death penalty that you were under. You agree to an unbelievably lop-sided exchange: your life of sinfulness and being under the death penalty for His righteousness and eternal life. You give Him your life of bondage to sin, and He gives you His life of freedom from sin.
You do not have to change yourself before coming to Christ. In fact, it is impossible for you to truly change your sinful nature apart from Christ. Our part is belief, trust, and surrender. His job is the change. But know that change will happen. A person who has put their faith and trust in Jesus will become like Him as that old sinfulness is replaced by righteousness. Some of that change may be apparent immediately. Other changes will happen over a lifetime. Some will be sudden and abrupt. Others will be almost imperceptible.
If you have no desire to change, then this is not the path for you. But if you’re tired of carrying around the weight of your sin, if you so desperately want to be free, if you don’t know why you keep making the wrong choices over and over again, I have great news: there is a solution, and His name is Jesus.