Indeed it is so often said that a frail fallen human being couldn't carry such a heavy load as the church which Peter is charged to carry, yet what do you make of Abraham? Was he not a frail fallen human being and he is said to be the father of all the faithful and it is in his bosom that the faithful dead are said to reside awaiting the resurrection. Surely logic says he could not bear such a load.
A certain man was wealthy, and he was clothed in purple and in fine linen. And he feasted splendidly every day. And there was a certain beggar, named Lazarus, who lay at his gate, covered with sores, wanting to be filled with the crumbs which were falling from the wealthy man's table. But no one gave it to him. And even the dogs came and licked his sores. Then it happened that the beggar died, and he was carried by the Angels into the bosom of Abraham. Now the wealthy man also died, and he was entombed in Hell. Then lifting up his eyes, while he was in torments, he saw Abraham far away, and Lazarus in his bosom. And crying out, he said: "Father Abraham, take pity on me and send Lazarus, so that he may dip the tip of his finger in water to refresh my tongue. For I am tortured in this fire." And Abraham said to him: "Son, recall that you received good things in your life, and in comparison, Lazarus received bad things. But now he is consoled, and truly you are tormented. And besides all this, between us and you a great chaos has been established, so that those who might want to cross from here to you are not able, nor can someone cross from there to here." And he said: "Then, father, I beg you to send him to my father's house, for I have five brothers, so that he may testify to them, lest they also come into this place of torments." And Abraham said to him: "They have Moses and the prophets. Let them listen to them." So he said: "No, father Abraham. But if someone were to go to them from the dead, they would repent." But he said to him: "If they will not listen to Moses and the prophets, neither will they believe even if someone has resurrected from the dead." (Luke 16:19-31)
So then, what shall we say that Abraham had achieved, who is our father according to the flesh? For if Abraham was justified by works, he would have glory, but not with God. For what does Scripture say? "Abram believed God, and it was reputed to him unto justice." But for he who works, wages are not accounted according to grace, but according to debt. Yet truly, for he who does not work, but who believes in him who justifies the impious, his faith is reputed unto justice, according to the purpose of the grace of God. Similarly, David also declares the blessedness of a man, to whom God brings justice without works: "Blessed are they whose iniquities have been forgiven and whose sins have been covered. Blessed is the man to whom the Lord has not imputed sin." Does this blessedness, then, remain only in the circumcised, or is it even in the uncircumcised? For we say that faith was reputed to Abraham unto justice. But then how was it reputed? In circumcision or in uncircumcision? Not in circumcision, but in uncircumcision. For he received the sign of circumcision as a symbol of the justice of that faith which exists apart from circumcision, so that he might be the father of all those who believe while uncircumcised, so that it might also be reputed to them unto justice, and he might be the father of circumcision, not only for those who are of circumcision, but even for those who follow the footsteps of that faith which is in the uncircumcision of our father Abraham. For the Promise to Abraham, and to his posterity, that he would inherit the world, was not through the law, but through the justice of faith. For if those who are of the law are the heirs, then faith becomes empty and the Promise is abolished. For the law works unto wrath. And where there is no law, there is no law-breaking. Because of this, it is from faith according to grace that the Promise is ensured for all posterity, not only for those who are of the law, but also for those who are of the faith of Abraham, who is the father of us all before God, in whom he believed, who revives the dead and who calls those things that do not exist into existence. For it is written: "I have established you as the father of many nations." (Romans 4:1-17)
