The Major Prophet Isaiah is not politically correct. He does not trim his words and add frills to it. He is not in the business of tying flamboyant rainbow ribbons to paper bags filled with feces. The Prophet Isaiah speaks the word of God as it comes to his mouth. Unadulterated, unfiltered, unhampered, unfettered, untampered, incontinent and raw. In all of their glory, Isaiah speaks the words of God.
But he who kills an ox is like one who slays a man;
He who sacrifices a lamb is like the one who breaks a dog’s neck;
He who offers a grain offering is like one who offers swine’s blood;
He who burns incense is like the one who blesses an idol.
As they have chosen their own ways,
And their soul delights in their abominations (Isaiah 66:3)
There are two categories of actions that Isaiah presents us with as readers and hearers of the word of God. On the left, we have actions that we deem as holy works because they are works we do with our hands. On the right, we have actions that we deem unholy because they are sins enumerated in the law of God that Moses told the people. The brilliance of Isaiah is that he sees no difference betwixt the two categories. The wages of sin are death. Every action on the right is widely known to be worthy of a death sentence. What is unbeknownst to the readers and hearers of this scroll is that the actions on the left, though they seem to grant life to the doers, are no different than the actions on the right.
God does not despise sacrifice qua sacrifice, but He does despise self-righteousness in sacrifice. The sacrifices we give unto God are due, but if we think they grant us life then we have substituted the Creator with His creation. Only God grants life. That is why in the Prayer of Religion we say "we believe in the Holy Spirit the lifegiver".
During this Nativity Fast, called the Fast of the Prophets in the Ethiopian Orthodox Tewahdo Church, we should take special care to listen to the words of the prophets daily. They hungered and thirsted for Orthodoxy, the righteous way (ፍኖተ ጽድቅ), which is Jesus Christ of Nazareth. Through our fasting we must hunger and thirst for Him as well. Fasting is a form of sacrifice that is easily input into Isaiah's formula above. Beware. Don't sleep, when it comes to relentlessly obeying the ordinances of God. We must never confuse God's grace with the works of our hands. Through God's grace we abstain from the abominations of this world, stand with the poor and grant Him our time for worship. Put God first, then your neighbor, then you. Perhaps, He will grant you eternal life.
Furthermore, we must love each other.