My Teacher

He established a decree in Jacob, and appointed a law in Israel, which he commanded our ancestors to teach to their children; that the next generation might know them, the children yet unborn, and rise up and tell them to their children, so that they should set their hope in God, and not forget the works of God, but keep his commandments; and that they should not be like their ancestors, a stubborn and rebellious generation, a generation whose heart was not steadfast, whose spirit was not faithful to God.
Psalm 78:5-8
George Santayana, though an atheist, said something that pertains to a great deal of scripture—especially the psalms which recount the history of God's people:  
Those who cannot remember the past are condemned to repeat it.  
He may have originated that well-known phrase, but it was Israel who first put forward the idea behind it. And of all the psalms, Psalm 78 is perhaps the best example of Israel remembering its past—this time not to celebrate it, but in order to grow from it. Throughout, we see God's faithfulness and the people's inconstancy, Israel's wrongdoing and God's forgiveness, human weakness and divine strength.
I may not be comfortable with the language of certain psalms. But I ignore them at my own risk, for they tell of a past I am doomed to repeat if I don't know it. Though born a Gentile, through the blood of Christ, I—along with all other believing Christians—am a child of Israel. The psalms are not just my songs of praise but also my teacher. In reciting them, I discover who I was, who I am now, and what God promises that I will be. I am fickle, but God is steadfast; I am a sinner, but Christ is my righteousness; I am weak, but the Holy Spirit grants me strength. Just as my history reminds me that I am far from perfect, it also tells me the good news of God's mighty acts for me, for all people, and for the world.
When I forget who I am, Lord, bring me back to my own story. When I think I can do no wrong, remind me of my mistakes. When I think I am without hope, tell me the good news of your love; in Jesus' Name, who taught me to pray: Our Father...