Christ is the Savior of the world,and His blood washes away our sins,and we receive the Spirit,and are saved.
But after we are saved then the responsibility falls on us to maintain that salvation,for God will not twist our arm to do right,but we must make the decision to keeping doing right.
Some will say that once we are saved we are always saved,and it is true that if we sin it can be forgiven,but the Bible says that if a person holds unto a sin they do not want to get rid of then the blood of Jesus cannot wash it away,and they erred from the truth,and are a sinner,and has to be converted,and it will save their soul from death,and the Bible says it would have been better if they had not known the truth than to turn from the holy commandments given to them,and they will be cut off if they do not continue in the goodness of God,and these people were saved,so why is there warnings.
The best defense for a person that believes in once saved always saved is not to put forth that sin does not effect our relationship with God,for it does,but if they said we might hold unto sin during our time with Jesus,but God will see to it that it is given up before we depart from this earth,but why the warnings if we will give up all sin before we depart from this earth.
God did not give warnings that those that hold unto a sin have eternal life,but they will not have it so good on earth,but if they hold unto a sin they will be cut off.
So the best defense is to say God will see to it that we give up all sin before we depart from this earth,but why the warnings of people being saved being cut off,and that is because they did not continue in God's goodness.
Rom 11:21 For if God spared not the natural branches, take heed lest he also spare not thee.
Rom 11:22 Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off.
2Pe 2:20 For if after they have escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ, they are again entangled therein, and overcome, the latter end is worse with them than the beginning.
2Pe 2:21 For it had been better for them not to have known the way of righteousness, than, after they have known it, to turn from the holy commandment delivered unto them.
2Pe 2:22 But it is happened unto them according to the true proverb, The dog is turned to his own vomit again; and the sow that was washed to her wallowing in the mire.
Jas 5:19 Brethren, if any of you do err from the truth, and one convert him;
Jas 5:20 Let him know, that he which converteth the sinner from the error of his way shall save a soul from death, and shall hide a multitude of sins.
Why the warnings towards the people that are saved.