Maybe the ones that complain that they did all this and all that their whole life so why should God let into heaven all those who didn't sacrifice anything at all to get there is like the workers
Mat 20:1-16 For like is the kingdom of the heavens to a man, a householder, who came out at the same time with the morning to hire workers for his vineyard." (2) Now, agreeing with the workers for a denarius a day, he dispatches them into his vineyard." (3) And, coming out about the third hour, he perceived others standing in the market, idle." (4) And to those he said, 'You also go into my vineyard, and whatsoever may be just I shall be giving you.' Now they came away." (5) Now, again coming out about the sixth and ninth hour, he does similarly." (6) Now, about the eleventh, coming out, he found others standing. And he is saying to them, 'Why stand you here the whole day idle?'" (7) They are saying to him that 'No one hires us.' He is saying to them, 'You also go into the vineyard.'" (8) Now, evening coming on, the lord of the vineyard is saying to his manager, 'Call the workers and pay them the wages, beginning from the last, to the first.'" (9) And, coming, those hired about the eleventh hour got a denarius apiece. " (10) And, coming, the first infer that they will be getting more. And they also got a denarius apiece." (11) Now, getting it, they murmured against the householder, (12) saying, 'These last do one hour, and you make them equal to us who bear the burden of the day and the scorching heat.'" (13) Yet he, answering one of them, said, 'Comrade, I am not injuring you! Did you not agree with me for a denarius? (14) Pick up what is yours and go away. Now I want to give to this last one even as to you. (15) Is it not allowed me to do what I want with that which is mine? Or is your eye wicked, seeing that I am good?'" (16) Thus shall the last be first, and the first last."
Of course the above scenario still is not quite equal to what we are talking about because the rest of mankind don't work at all and in fact neither do we of the nations. If we worked for the kingdom to get wages then grace is no longer grace.
But you get the point?