A quandary of the salvation is, “How does God, who is so merciful and loving that He will go to any length to save his creation, BUT is also so just and holy that sin cannot be allowed in His presence, reconcile sinful man back to Himself?” The answer lies in a system of salvation that 1.) will allow man to be justified and 2.) satisfies God’s mercy and graciousness, and His holiness and justice. To accomplish this man could be saved by a legal system. A man would be required to keep the law, without sin or fault and so be justified. This would satisfy the justice and holiness of God. So the a law was given, revealed, and accessible to the Jews; and all they had to do was keep it (Deut. 30:8-14). The problem was that no one kept it, Rom. 3:9,23. This was the fault of man, not the Law which was good, Ps. 119.
A System of Grace is what we need. With all under the penalty of sin, we need someone to do us a favor, to show us some grace. We need someone to pay the debt we owe, which would satisfy the demand of justice. The problem is that all men same debt. All men are equally debtors, so none can pay for his own sins nor the sins of anyone else. We need someone to pay the debt, we need a willing and equal substitute. To unwillingly take from one to give to another is robbery, so the one who pays the price for our sins has to be willing to pay the price for us (Rf. Jn.10:17,18). We needed in this system of grace is one who can pay the price for us. So the substitute must be debt free, sinless, without moral scar or blemish. This satisfies the holiness and justice of God and shows his marvelous grace. Here is the great grace of God — salvation in Christ, the sinless, willing and equal substitute. He paid the price for our sins! By grace are we saved, Rom. 4:4; 11:5,6.