Midrash su Salmi 118:20

He said: “The crooked cannot be mended, and deficiency cannot be counted” (Ecclesiastes 1:15) – in this world, one who is crooked can be mended, and one who is mended can become crooked. But in the future, one who is crooked cannot be mended, and one who is mended cannot become crooked. “And deficiency cannot be counted” – there are wicked ones who associate with one another in the world; one of them repented before his death, and one did not repent. It turns out that this one stands in the company of the righteous, and that one stands in the company of the wicked. He [the one who did not repent] sees him [the other one] and says: ‘Woe is me, perhaps there is favoritism in this matter? [Both] I and that one have stolen, both I and that one have killed; yet that one is standing in the company of the righteous, and this one [referring to himself] is standing in the company of the wicked.’ They [the angels] respond and say to him: ‘Fool of the world, you were despicable, and you were cast aside after your death for three days; did they not drag you to the grave with ropes? “Beneath you maggots are spread and worms are your cover” (Isaiah 14:11). When your friend understood this, he repented from that path. You, too, had the opportunity to repent, but did not do so.’ He says to them: ‘Allow me to go and repent,’ and they respond to him and say: ‘Fool of the world, do you not know that this world is like Shabbat, and the world from which you came is like the day before Shabbat. If a person does not prepare on the day before Shabbat, what will he eat on Shabbat? Moreover, this world is like the sea, and the world from which you came is like dry land. If a person does not prepare on dry land, what will he eat at sea? Moreover, this world is like the wilderness, and the world from which you came is like civilization. If a person does not prepare in civilization, what will he eat in the wilderness?’ What does he do? He folds his hands and eats his flesh, as it is stated: “The fool folds his hands and eats his flesh” (Ecclesiastes 4:5). He says: ‘Allow me to see my friend in his glory [in heaven].’ They say to him: ‘Fool of the world, we are commanded from the mouth of the Almighty, that the wicked will not stand alongside the righteous, and not the righteous alongside the wicked, not the impure alongside the pure, and not the pure alongside the impure. About what are we commanded? It is about this gate, as it is stated: “This is the gate of the Lord; the righteous shall enter into it”’ (Psalms 118:20).

Scripture states: This is the gate of the Lord, the righteous shall enter into it (Ps. 118:20). Who are the righteous ones that will enter? The faithful ones, as it is said: Open ye the gates, that the righteous nation that keepeth faithfulness may enter in (Isa. 26:2). This is the gate that the faithful enter, as it is said: It is a good thing to give thanks unto the Lord, and to sing praises unto Thy name, O Most High, to declare Thy loving-kindness in the morning (Ps. 92:2). What is written after that? For Thou hast made me glad. What makes us glad? It is the faith which our fathers professed in this world, which is all night, as it is written: And thy faithfulness in the night seasons (ibid., v. 3). And it is also written: But the righteous shall live by his faith (Hab. 2:4), and They are new every morning, great is thy faithfulness (Lam. 3:23).

12) "which a man shall do": R. Yirmiyah was wont to say: Whence is it derived that even a gentile who observes the Torah is like the high-priest? From "which a man (any man) shall do, and he shall live in them." It is not written: This is the Torah of Cohanim, Levites, or Israelites," but (II Samuel 7:19) "And this is the Torah of man, O L–rd, G d." And thus is it written (Isaiah 26:2) "Open, ye gates, and let there come" — Cohanim, Levites, and Israelites is not written, but — (Tehillim 118:20) "tzaddikim shall come therein." And (Tehillim 33:1) "Sing, tzaddikim in the L–rd" — not Cohanim, Levites, and Israelites. And (Tehillim 125:4) "Do good, O L–rd, to the good" — not "to Cohanim, Levites, and Israelites." Even a gentile who observes the Torah is like the high-priest.