Our "heads held high"
Leviticus 26:11-13 says,
"I will put my dwelling place [tabernacle or presence] among you, and I will not abhor you [because of your sin]. I will walk among you and be your God, and you will be my people. I am the Lord your God, who brought you out of Egypt so that you would no longer be slaves to the Egyptians; I broke the bars of your yoke and enabled you to walk with heads held high."
These words are spoken to Israel by their covenant God Yahweh to remind them that he redeemed them from slavery in Egypt, and that now they are his. He gave them his holy law to show them that to live with him now or be in fellowship with God they must be holy as he is holy. But they could not keep their part of the covenant. There is grace in law because through the law we know we are sinners, because none of us keep it perfectly. And therefore we need grace. Israel kept breaking the marriage covenant with their husband, their covenant God, and God kept punishing them for their disobedience showing them that their hearts were sinful and not able to obey him. So because of their constant disobedience to God's law and covenant, their life and fellowship with God has been on the rocks and always interrupted. But there must be another way of coming close and staying close to God. In Chapter 26 we read that under the old covenant God promised to his ancient people material blessings if they obeyed him, and punishments If they disobeyed him. Through the holy law of God we all know we come short and never measure up, and now under the New Covenant, God doesn't deal with us on the bases of tit for tat, we scratch his back and he'll scratch our back, I will be a good person and he will be good to me. No, our good is never good enough. But, God promised a remnant in Israel who would obey him, and since all have sinned and are imperfect, a substitute was provided, the man Christ Jesus, the perfect Israelite. God's Son a man like us but without sin, came in our place, did our part, and perfectly kept the covenant with God for us as our representative. And now we're accepted by God and in fellowship with God because Jesus obeyed in our place. This is grace. This is the gospel. This is freedom. This truth helps us keep our heads high, and not slouch as miserable disobedient children. God now sees us in Christ's perfect righteousness, through our faith in him. Now we can breathe and enjoy God and the life he's given us. We fear/reverence him, but no need to be afraid of him. But when we sin and fail God, instead of simply confessing it to God and accepting his gracious forgiveness, we have a tendency to forget his grace and go back to tit for tat, I obey and he'll bless me, I'll disobey and he'll punish me. That is why we need to look at Jesus in a right way, and preach the good news about him to ourselves and to each other every day, because we are prone to forget him.
Because of Jesus' perfect obedience in our place NOW we can have perfect confidence in God's promise to us who trust in Jesus: "I will put my dwelling place [tabernacle or presence] among you, and I will not abhor you [because of your sin]. I will walk among you and be your God, and you will be my people [in a covenant relationship]." And so "our heads [are] held high", so that we can walk with confidence and humility only by God's grace through faith in Jesus Christ.