The four openings that Abraham has are the openings of the heart. Abraham's heart is open as a hall to every person wherever he is, for all his troubles and mental difficulties. Even a person full of constant anger and frustration, a person who does not have a single moment of peace of mind and calm, knows that there is a place in Abraham's heart for him, that meeting him will calm his stormy spirit.
Another Ruth in the tent of Abraham is open to a man who has sunk in terrible impurity, in sins and terrible injustices, until he has lost all faith in himself and in the world, until he is unable to even imagine a more ideal world, a clean and pure world. He too knows the right address He also knows that in Abraham's tent he will find those who sing it in the tassels of his head, express full confidence in him and march him to the path of righteousness.
Another spirit will be wide open to all needy, poor, hungry and thirsty. And even the same person who has lost the meaning of his life and its meaning, he too has an open Ruth in the heart of Abraham, also he knows that Abraham will help him find and discover value for his life in the world. Abraham's speech, his caress and his smile, all have the power to lift man from the depths of his troubles and illuminate his path.
When a man sits in his house alone and lonely, alone in his world, and feels all the weight of the terrible loneliness, he goes to Hebron and enters Abraham's abode. He sits next to him, and the same old man opens a conversation with him. Not a few moments pass and the same person suddenly feels that he is no longer alone in the world, he feels as if he is now sitting next to his father, he sees how much Abraham cares about him, what concern he has for him. This is the true power of our ancestor Abraham.
From "Tzur Hatzvam"
Rabbi Eli Horowitz