An altar is any structure upon which offerings such as sacrifices are made for religious purposes. It was usually a raised platform with a flat surface. There are over four hundred references to altars in the Bible. The word altar is first used in Genesis 8:20 when Noah built an altar to the Lord after leaving the ark. However, the idea was present as early as Genesis 4:3–4 when Cain and Abel brought their sacrifices to the Lord. They most likely presented their offerings on some type of altar, even though the word altar is not used in that passage.
An altar always represented a place of consecration. Before God gave His Law to Moses, men made altars wherever they were out of whatever material was available. An altar was often built to commemorate an encounter with God that had a profound impact upon someone. Abram (Genesis 12:7), Isaac (Genesis 26:24–25), Jacob (Genesis 35:3), David (1 Chronicles 21:26), and Gideon (Judges 6:24) all built altars and worshiped after having a unique encounter with God. An altar usually represented a person’s desire to consecrate himself fully to the Lord. God had worked in a person’s life in such a way that the person desired to create something tangible to memorialize it.
During times of Israel’s rebellion and idolatry, the Lord’s altars fell into disrepair. The prophet Elijah, confronting the prophets of Baal on Mt. Carmel, “repaired the altar of the Lord, which had been torn down” (1 Kings 18:30). Elijah’s restoration of the altar was significant, given the rampant paganism of his day. Also, in spite of the fact that he was living in a divided kingdom, the prophet symbolized the unity of God’s people in his construction: “Elijah took twelve stones, one for each of the tribes descended from Jacob, to whom the word of the Lord had come, saying, ‘Your name shall be Israel.’ With the stones he built an altar in the name of the Lord” (1 Kings 18:31–32). It was on this rebuilt altar that God rained down fire and put the Baal-worshipers to shame (verses 38–39).
Sometimes God Himself commanded that an altar be built after He had delivered someone in a miraculous way (Deuteronomy 27:4–7; Exodus 30:1). Such an altar would be a memorial to help future generations remember the mighty works of the Lord. Because atonement is God’s work, the Law specified that an altar made of stones must be made with natural, uncut stones, “for you will defile it if you use a tool on it” (Exodus 20:25).
When God gave instructions for the tabernacle, He also gave detailed instructions for the kind of altar the courtyard should contain (Exodus 27:1–8). On this altar, the people made sacrifices that God accepted as atonement for their sin. It was to have four horn-like projections, one at each corner. It had to be large enough to hold sacrifices of bulls, sheep, and goats. For the temple that Solomon built, the altar was made of pure gold (1 Kings 7:48).
In the broadest sense, an altar is merely a designated place where a person consecrates himself to someone or something. Many church buildings have “altars” for prayer, communion, weddings, and other sacred purposes. Some Christians create their own “altars” for personal worship as visible reminders of Romans 12:1, which says to “present yourself as a living sacrifice.”
Every human heart has an invisible altar where the war between the flesh and the spirit rages. When we surrender areas of our lives to the control of the Holy Spirit, we are in effect laying that area on the altar before God. It can help to visualize Abraham’s altar where he offered his son Isaac to the Lord (Genesis 22:9). We can ask the Lord what areas of our lives He is requiring that we offer to Him. We can symbolically lay that on the altar and let go. We don’t need a flat-topped surface; we can surrender our lives to God on the altar of our hearts at any time.