Sorry that I havn't been around the forum for a bit, but this "by this grace alone" is simply wrong. Even according to the scriptures you quoted. Of course I have already pointed this out to you, but you have been ignoring it. You quoted:
Ephesians 2:8 For by grace are ye saved through faith; and that not of yourselves:
it is the gift of God:"
How is it you miss "through faith" in the above verse? You need to ask yourself this question.
Here is another place that might help you.
Romans 1:1,2 Therefore, having been justified by faith, we have peace with God through our Lord Jesus Christ, though whom also we have obtained our introduction by faith into this grace in which we stand...
Now we like to point out that importance of God's grace because we are not saved by works, and that is correct. But God's grace is part of His personality so it is available to everyone, but is not obtained by everyone. It is only obtained by those who have faith in Him. So we don't obtain salvation by works, but we do obtain salvation by faith. Of course nobody could obtain salvation by any means except for God's grace, but even now you must have faith, so it is not by grace alone. That is simply a statement that sounds good but is not correct.
The serious problem with the statement is that many seem to think that they have salvation no matter what they do. That is not so!!! It would be so if it was simply a matter of God's grace, but because it also take faith not everything is ok. For example, it is not ok to never hear from the Lord! A person that believes that God exist with them will certainly hear from Him who does exist with him. Abram heard from the Lord in a vision and believed that is was the Lord and that belief was counted to Abram as righteousness. That belief in God cause Abram to take numerous actions in his life. So it was not ok for Abram to simply do anything all the time. Because Abram believed he listen to the Lord and at times that hearing God by faith resulted in actions taken based upon what he heard.
So does a person really thinking it was by grace alone and not showing any concept of hearing the Lord by faith and doing what He tells them acting like an off spring of Abraham?
Certainly God did not have to credit Abram with righteousness simply because he believed. By the grace of God Abram was counted as righteous, but that only because He believed. It doesn't take work to believe, it takes faith. If takes faith the God actually exists and not as some far off being in a place called heaven, but as an Omni-present being who is with you so can be heard from. And if you really believe God can be heard from you will listen to Him and at least want to do what He tells you, because you believe Him who talks to you is God. So you won't do just anything, because you will fear Him. And you will want to do what He asks because you love Him with whom you have developed a relationship with.
So it was that James wrote, Jm 2:14 What use is it, my brethren, if someone says he has faith but he has no works? Can that faith save Him?
So it is by faith which we are saved! That of course because God has grace, because are works will never be good enough. Never-the-less we will have works of faith, which is to says we will hear the Lord telling us to do this and that and we will do them because of our faith. Which brings us to the other thing that James wrote:
Jm 2:20 But are you willing to recognize, you foolish fellow, that faith without works is useless?
So there is one that does works without hearing the Lord, so God is not really their Lord. God's grace does not cover that person.
And there is one that does not do works because he believes that it is by grace alone, but God's grace does not cover that person either.
In both those cases faith is missing. God's grace covers those that have faith. That faith results in getting instructions from the Lord and works of faith come from that. And type of faith saves use because God has grace. Our works are never good enough, but because of God's grace our faith is. Still, that faith results in actions, because it results in getting instructions from God.