The Lord remembers his covenant forever (Psalm 105). God made covenants with his people in the Old Testament. God promised Abraham he would be the father of many nations. He promised to be their God from Abraham to his descendants. It was an everlasting covenant and it was binding.
Today we have the Scriptures and there are no more books that will be added to the Bible we use every day, but God is still writing. He is writing our book. It is titled with our name. It is his words to us and our responses to him. Maybe it would start this way:
God spoke to me and said, My covenant with you is this: I sent my son Jesus to die on the cross for your sins. I will forgive your sins and remember them no more. You are forgiven. It is my everlasting promise to you. Look to the Lord for your strength. Seek to serve him constantly. Recall the wondrous deeds that he has done for you, his promises and his judgments. Seek me with your whole heart, soul, mind and body and love your neighbor as yourself. Teach your children about me so that generations to come will know of my love for you.
God does write your book. There will be good chapters and chapters that are hard to go through but when you get to the end of your life we all want to hear “Well done, good and faithful servant.”