I guess if we do not let the Scriptures explain itself, we end up with a thread full of accusations and insults. I would think that it is a cause for disappointment to Yahweh to see some of these conversations. Hopefully, this small explanation helps someone with getting the "big picture" of our salvation - the beginning, anyway.
Yahweh used the principle of covenants to establish promised between Himself and His people. The ceremony that occurs to prove it's enactment frequently required a penalty for failure. Usually, that penalty included death and blood. When God promised Abram the lands for Israel, He made a covenant that required blood:
Ge 15:7–21 And he said to him, “I am the LORD who brought you out from Ur of the Chaldeans to give you this land to possess.” But he said, “O Lord GOD, how am I to know that I shall possess it?” He said to him, “Bring me a heifer three years old, a female goat three years old, a ram three years old, a turtledove, and a young pigeon.” And he brought him all these, cut them in half, and laid each half over against the other. But he did not cut the birds in half. And when birds of prey came down on the carcasses, Abram drove them away. As the sun was going down, a deep sleep fell on Abram. And behold, dreadful and great darkness fell upon him. Then the LORD said to Abram, “Know for certain that your offspring will be sojourners in a land that is not theirs and will be servants there, and they will be afflicted for four hundred years. But I will bring judgment on the nation that they serve, and afterward they shall come out with great possessions. As for you, you shall go to your fathers in peace; you shall be buried in a good old age. And they shall come back here in the fourth generation, for the iniquity of the Amorites is not yet complete.” When the sun had gone down and it was dark, behold, a smoking fire pot and a flaming torch passed between these pieces. On that day the LORD made a covenant with Abram, saying, “To your offspring I give this land, from the river of Egypt to the great river, the river Euphrates.......”
The sign of the covenant between Yahweh and Abram's people was circumcision.
Ge 17:9–11 And God said to Abraham, “As for you, you shall keep my covenant, you and your offspring after you throughout their generations. This is my covenant, which you shall keep, between me and you and your offspring after you: Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskins, and it shall be a sign of the covenant between me and you.
If we go back to Mount Sanai and Moses' trip to the mountain top, we know that Yahweh offered the Old Covenant to the Hebrew people. The deal was, if the people agreed to be bound to and obey those commandments, they would be His people. Thousands did.
Ex 24:3–8 Moses came and told the people all the words of the LORD and all the rules. And all the people answered with one voice and said, “All the words that the LORD has spoken we will do.” And Moses wrote down all the words of the LORD. He rose early in the morning and built an altar at the foot of the mountain, and twelve pillars, according to the twelve tribes of Israel. And he sent young men of the people of Israel, who offered burnt offerings and sacrificed peace offerings of oxen to the LORD. And Moses took half of the blood and put it in basins, and half of the blood he threw against the altar. Then he took the Book of the Covenant and read it in the hearing of the people. And they said, “All that the LORD has spoken we will do, and we will be obedient.” And Moses took the blood and threw it on the people and said, “Behold the blood of the covenant that the LORD has made with you in accordance with all these words.”
But then Yahweh had Moses go up the mountain to receive the stone tablets with the commandments. While up there, these Hebrew people convinced Aaron to create an idol - a golden calf. God was very displeased:
Ex 32:27–35 And he said to them, “Thus says the LORD God of Israel, ‘Put your sword on your side each of you, and go to and fro from gate to gate throughout the camp, and each of you kill his brother and his companion and his neighbor.’ ” And the sons of Levi did according to the word of Moses. And that day about three thousand men of the people fell. And Moses said, “Today you have been ordained for the service of the LORD, each one at the cost of his son and of his brother, so that he might bestow a blessing upon you this day.” The next day Moses said to the people, “You have sinned a great sin. And now I will go up to the LORD; perhaps I can make atonement for your sin.” So Moses returned to the LORD and said, “Alas, this people has sinned a great sin. They have made for themselves gods of gold. But now, if you will forgive their sin—but if not, please blot me out of your book that you have written.” But the LORD said to Moses, “Whoever has sinned against me, I will blot out of my book. But now go, lead the people to the place about which I have spoken to you; behold, my angel shall go before you. Nevertheless, in the day when I visit, I will visit their sin upon them.” Then the LORD sent a plague on the people, because they made the calf, the one that Aaron made.
The Hebrew people failed Yahweh and did not live up to His commandments and God would have to reconcile them to Him each time. He gave them the sacrificial acts in order to cover their sins. As it turned out, the people would not learn to live without sins. Kind of like we are today, when things get good in our world, we tend to forget Yahweh.
Remembering back to the book of Genesis, we see that Yahweh had prophesied that a man born of woman would arise to defeat the Serpent. This man was mentioned several times in the Old Testament and the prophecy continued. Along with the other prophets, a prophet named Isaiah told us quite a bit about about Him. We are told that we will have a New Covenant and, different from the Hebrews under the old one, those who submitted to the New Covenant will have God's spirit and will have God's words written on their hearts. (clean conscience - see 1 Peter 3:21)
This man foretold in Isaiah was born to a virgin names Mary. Yahweh was His Father. Yeshua (who we call Jesus) came with a purpose. He was to introduce the Kingdom of God. It is the New Covenant. Again, as it was with the Old Covenant, we have to accept our part in it to become children of Yahweh. (Buried with Christ and risen as a new creature) Instead of stone tablets, we have every word that came from the mouth of the Messiah. Those words originated with His Father - the only true God.
As the book of Hebrews points out, a covenant is not in effect without the shedding of blood.
Heb 9:22. Indeed, under the law almost everything is purified with blood, and without the shedding of blood there is no forgiveness of sins.
The Hebrew people had to suffer the penalty for violating the Sinai (Moses) Covenant. Jesus was the spotless lamb that died to pay that penalty and enact the New Covenant.
Mt 26:26–29 Now as they were eating, Jesus took bread, and after blessing it broke it and gave it to the disciples, and said, “Take, eat; this is my body.” And he took a cup, and when he had given thanks he gave it to them, saying, “Drink of it, all of you, for this is my blood of the covenant, which is poured out for many for the forgiveness of sins. I tell you I will not drink again of this fruit of the vine until that day when I drink it new with you in my Father’s kingdom.”
As for work, that much hated four-letter word, there is "a work" that we are expected to do.
John 6:27–40 Do not work for the food that perishes, but for the food that endures to eternal life, which the Son of Man will give to you. For on him God the Father has set his seal.” Then they said to him, “What must we do, to be doing the works of God?” Jesus answered them, “This is the work of God, that you believe in him whom he has sent.” So they said to him, “Then what sign do you do, that we may see and believe you? What work do you perform? Our fathers ate the manna in the wilderness; as it is written, ‘He gave them bread from heaven to eat.’ ” Jesus then said to them, “Truly, truly, I say to you, it was not Moses who gave you the bread from heaven, but my Father gives you the true bread from heaven. For the bread of God is he who comes down from heaven and gives life to the world.” They said to him, “Sir, give us this bread always.” Jesus said to them, “I am the bread of life; whoever comes to me shall not hunger, and whoever believes in me shall never thirst. But I said to you that you have seen me and yet do not believe. All that the Father gives me will come to me, and whoever comes to me I will never cast out. For I have come down from heaven, not to do my own will but the will of him who sent me. And this is the will of him who sent me, that I should lose nothing of all that he has given me, but raise it up on the last day. For this is the will of my Father, that everyone who looks on the Son and believes in him should have eternal life, and I will raise him up on the last day.”