Question. If the Law of God is perfect, as Psalms 19:7 says, where is giving in the law?
Law is never given in, as it's never a necessity to give in the Law.
God has an absolute set of Law for the judgment of both humans and angels. Satan and Adam broke this set of Law. Since then humans are living in a realm Satan has a deep influence. It is proven through Adam till Noah that when humans are put in such a realm they can't abide by God's Law. It means when judged by God's absolute set of Law, no humans are savable. Earth originally is intended as "God's field for the harvesting of human souls", that is, earth is for God to produce humans to be brought to an eternal realm we call heaven. His this purpose is defeated when can no longer produce humans who can go passing the final judgment to enter heaven. When this sole purpose of earth is defeated, earth shall be destroyed. This is the story of Noah.
On the other hand, if earth is destroyed it signifies that God's plan has failed and Satan wins. However it's not yet, God introduced the series of covenants by the blood of Christ to be shed. Generally speaking, the purpose of Law (any set of them such as Mosaic Law) is to serve the purpose of identifying the righteous from the wicked. If it's this purpose is defeated, that is, under this set of Law that no humans can be saved, then it's about time for a newer covenant to be signed off. When the absolute set of Law of God can no longer save the righteous, God grants a covenant with a set of Law capable of identifying the righteous such as Noah and his family. This set of Law come with Noah's covenant remains to be our conscience and moral code embedded in our hearts. It is called God's Law written in our hearts.
God then grants another set of Law (Mosaic Law) to the Jews. It's a written set of Law which makes it easier for the Jews to follow. It by no means says that the Jews no longer need to follow their conscience to act. The Mosaic Law is added upon humans' conscience. That is to say, the Law embedded in a previous covenant doesn't simply go away. This previous Law may not save you (efficiently) though. Similarly, when New Covenant is accepted by a Christian, it by no means says that he doesn't need to follow conscience and moral code to act. It only means that under the circumstance that he can no longer rely on the older covenant to be saved, he can now choose to be under the protection of the New Covenant.
Matthew 5:17 (NIV2011)
17 “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them.