What was God's main controversy with the nation of Israel in Isaiah?
God's controversy with Israel was that their meticulous temple worship and religious correctness were devoid of faith. They performed every rite to the last jot and tittle, yet their hands were full of blood, and their religion had become dead. God sought simple faith, not outward ritual alone.
Les explains that the major point of controversy was not that Israel neglected temple worship. They would not dream of approaching temple worship and not do it exactly right; to the last jot and tittle, they did it right. But what were they lacking? Faith. There was no faith associated with all this, and it had become nothing but a dead religion. God says He was weary, would hide His eyes, and would not hear their many prayers because their hands were full of blood. Les also parallels this to Christendom, which has all the rigmarole but few people with faith to appropriate the real truth. Paul likewise was a religious Jew doing everything according to the Book, yet he was destitute of real faith and blind about who he was and who Jesus really was. God is looking for simple faith.
And when ye spread forth your hands, I will hide mine eyes from you: yea, when ye make many prayers, I will not hear: your hands are full of blood.