Halakhah sobre Isaías 1:11

Moreover, during the time of the First Temple many people mistakenly regarded the offering of korbanot as idolatrous acts possessing magical powers, able to grant good fortune in matters such as livelihood, health, and the abolishment of evil decrees. The prophets severely condemned this misguided notion and taught that a korban in its essence, is an expression of the people’s desire to get closer to God through total devotion. That is the primary purpose of humanity in this world, as The torah states (Devarim 10:12): “What does God want of you? Only that you revere the Lord your God, follow all His ways, love Him, and serve the Lord your God with all your heart and with all your soul.” When the person who brings the offering does not demonstrate true devotion to God nor the desire to improve, not only is the offering ineffective, but it is repulsive in God’s eyes, as it is written: “‘Why do I need all your sacrifices?’ God asks. ‘I am sated with your burnt offerings of rams and the fat of fed beasts, and I have no desire for the blood of cattle, sheep, and goats. When you appear before Me, who asked you to do this, trampling My courts? Do not bring any more vain meal offerings; incense is offensive to Me…’” (Yeshayahu 1:11-13). By instituting the prayers, the Men of the Great Assembly restored the proper priorities to the worship of God, reminding us that faith, focus, and devotion are primary. These values indeed find their clear expression in the prayers, as R. Elazar said, “Prayer is greater than sacrifices” (Berakhot 32b). By emphasizing our kavana, we pray to God that He rebuild the Temple speedily in our time so that we may express our devotion to Him fully – through both prayer and sacrifice.

One who wants to pray a voluntary prayer needs to know oneself to be quick and careful, and estimate in one's opinion that one will be able to concentrate in one's prayer from beginning to end. But if one is not able to concentrate well, we would consider it [like] "Why do I need all your sacrifices?" (Isaiah 1:11), and [say] would that one could concentrate on the 3 fixed prayers of a day [before trying to do something extra]!