Romans 9:12

8 So it is not the children of the flesh who are God’s children, but it is the children of the promise who are regarded as offspring.

9 For this is what the promise stated: “At the appointed time I will return, and Sarah will have a son.”

10 Not only that, but Rebecca’s children were conceived by one man, our father Isaac.

11 Yet before the twins were born or had done anything good or bad, in order that God’s plan of election might stand,

12 not by works but by Him who calls, she was told, “The older will serve the younger.”

13 So it is written: “Jacob I loved, but Esau I hated.”

14 What then shall we say? Is God unjust? Certainly not!

15 For He says to Moses: “I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.”

16 So then, it does not depend on man’s desire or effort, but on God’s mercy.

Read all of Romans 9