Abraham's inner response to God was expressed outwardly in worship through the offering of sacrifices. He built altars on which to offer sacrifices to God at Shechem and near Bethel (Genesis 12: 6-8). He was prepared to make the sacrifice of his son Isaac (Genesis 22). In the stories of Jacob as a young man, Jacob offers a sacrifice of oil to God, pouring it out on the stone he had slept on while he dreamed of the stairway that stretched up to heaven, to the presence of the God of his father and grandfather (Genesis 28: 10-22). Jacob offered an animal sacrifice when he vowed never to fight his father-in-law, Laban (Genesis 31: 45-55). Towards the end of his life he offered sacrifices at Beersheba before he moved into Egypt.

The Hebrew word for 'altar' comes from the verb 'slaughter', which indicates to us that the shedding of blood was associated with sacrifice. Every religion has its forms through which the worshipper approaches God, and the concept of making an offering to God is a very widespread one. The most ancient and the simplest understanding of sacrifice was of providing a meal for a god. An offering can be made to show thanks, to share in a sense of being in fellowship with God, or to express a sense of guilt and own a desire for forgiveness. Something of value is offered, and we understand how it was that the Patriarchs offered animal sacrifices because their wealth was in their herds of animals. In their understanding, the blood of the animal was equated with its life. By killing it, the life of the animal was offered back to its creator, acknowledging at God alone is the source of life.

It is more difficult to understand the idea of burning the sacrifice after the animal as been killed, but this is found in African traditional religions. The complete destruction of the sacrifice by fire can express the acknowledgement of God as the only source of life, the only creator, the one almighty God. The action may express the idea that nothing can be held bad from God or hidden from him. The worshipper expresses total commitment to God as his offering is consumed by the fire.

In Genesis 31: 45-55, we read that Jacob invited the men with whom he worshipped to share a sacrificial meal (verse 54). In this case the sacrifice was not totally burnt but part of it was eaten by the worshippers and this brought them a sense of fellowship or communion with God. In later Israelite religion, we find both burnt offerings and sacrificial meals.

In later Israelite religion the idea of guilt offering, or an atonement offering, became important. The animal offered was a substitution for the man who offered it. By placing his hands on the animal the man believed that his life-force and his sins were transferred to the "animal which was then killed leaving the man purified or 'clean' of sin.

What have archaeologists to say about sacrificial practices in the ancient Middle East in the first half of the second millennium B.C.? According to Roland De Vaux, burnt sacrifices were not found in Mesopotamia but were found amongst the Moabites, Ammonites, Canaanites, and Israelites. Evidence for human sacrifice is rare, but there is some evidence for child sacrifice amongst the Ammonites who worshipped a god named Milcom. Later in Israel's history, we find the grim story of how a king of Moab sacrificed his son to try to obtain victory in battle (2 Kings 3: 27). Excavations at Megiddo have revealed a great circular high place, reached by a flight of steps. In this high place, which was the place of sacrifice to a god, a large quantity of burnt animal bones has been found.

In agricultural areas, such as those along the banks of the great rivers, food offerings were sacrificed. These could be the first gatherings of a harvest, or be in the form of a meal offered to a god. Incense was also burned to make a sweet smell to attract the god's attention.

What led to particular places being chosen for the setting up of altars made of stones? If we turn again to the Patriarchal narratives we find that Jacob set up his stone at a place where God had appeared to him in a dream and where he vowed peace with his father-in-law. Abraham offered his sacrifice (Genesis 15) where God had spoken to him, and prepared to offer sacrifice where God had shown him that his faith must be tested (Genesis 22). He built the altar at Shechem, in the hill country of Canaan, after God had appeared to him and spoken to him. From these examples we can see that a strong reason for setting up an altar and regarding a place as holy, was the experience of a theophany (a manifestation of God's presence) to the worshipper. Where a vision of God was received, or God's voice was heard, that place became holy. The altar built at that place became a meeting place between the man and God, and the sacrifice offered there was a means of approaching God. The altar might be one stone or several together.

In African traditional religions we do not hear much about stone altars but much more about holy places. A tree, a hilltop or mountain top, a rock or face of rocks, could be regarded as holy. In Kikuyu tradition, the sacrifice and burnt offering of a chosen sheep or goat was made at the foot of a sacred tree in times of crisis or on important occasions. There would be a good reason why a certain place or thing was regarded as a shrine; it would be associated in some way with the power of the spirit world or the power of God.

We shall return later to the significance and, also, the abuse of sacrifice in worship when we look at the great prophets, but the following ideas are connected with sacrifice of different kinds. A sacrifice could be offered as a gift, or even a meal, to the god. If the worshipper ate some of the meat of the sacrifice he could feel united with the god through sharing the sacrificial meal. The animal offered could be regarded as a substitution for the man offering it. In shedding the blood of the animal the life-force was offered back to the god as the most precious thing which could be offered.

At a higher level of religious understanding, there should be a recognition behind the action of offering sacrifice that God is Lord of all things and creator of all life; therefore man can give God nothing that God has not created. Man voluntarily deprives himself of something which he values and offers it back to God, who made it, as a sign of gratitude and dependency on God. In the acceptance of a sacrifice, God binds himself to the man who offers it. Sacrifice should be offered with the fullest purity of intention. In the story of God's command to Abraham to sacrifice Isaac we find the full purity of Abraham's intentions towards God being tested to the utmost. God's greatest gift to Abraham was to be offered back to God.

From these various ideas we can identify four main purposes of sacrifice. Sacrifice is offered as thanksgiving for favours received, a request for continued favours, in propitiation for sin and wrongdoing, and in adoration of the God on whom man depends absolutely.