The Bible says that "there are many gods, and many lords, yet for us there is but one God…" (1 Corinthians 8:5) There are, indeed, many religions in the world and many deities, besides the one, true God revealed in the Bible. But at a deeper level, there are really only two alternatives, two beings between whom we must choose to serve. Do not quickly jump to the conclusion that those two basic alternatives are God and Satan. It is quite true that if we don't serve God we serve Satan, but that is a mere accident or by-product of the fundamental alternative. Few people on earth knowingly and purposely serve Satan. His known character and conduct are so bad that only an especially perverse and depraved mind would willingly serve him. Others claim to serve Satan when they don't even believe he exists. He just serves as a way to thumb their noses at the God of the Bible. In effect, they're saying, "God is a kill-joy; Satan is all about having fun!"
A saying of Jesus gets us closer to the answer: "No one can serve two masters; for either he will hate the one and love the other, or he will be devoted to one and despise the other. You cannot serve God and Mammon." (Matthew 6:24) "Mammon" is an Aramaic term for worldly wealth. But why do many people want worldly wealth? Is it not that they think this will bring them pleasure since the chief pleasures of this world are often thought to be obtained by money? But what about those who are content with "simple pleasures" such as going for walks in the woods, holding a newborn baby, relaxing in a hammock on a summer's day? They surely do not worship Mammon yet they are not necessarily serving God. What, then, are the basic two alternatives?
Obviously, God is the first alternative, but who or what is the second? The ultimate alternative to the true and living God for you is not Satan or worldly wealth but it is you! For me it is me. In that sense, I suppose, there are ultimately indeed "many gods, and many lords" other than the one, true God. But for each of us, there are really only two alternatives: we serve either God or ourselves. But how do we know whom we are serving? If we cannot serve both God and ourselves at the same time then there must be some way to tell which one we presently serve. I suggest that the Old Testament sacrificial system gives us an important clue.
Under the Old Covenant, the people of Israel were commanded to offer sacrifices to God. The New Testament writers point out that these sacrifices symbolized and foreshadowed the coming of the one true sacrifice for sin: the sufferings and death of the Messiah who, it turns out, was Jesus. However, there was also a principle of worship that the sacrifices and offerings illustrated. The principle is this: we sacrifice the lesser on behalf of the greater. In Bible days a man's goods consisted in things like cattle, grain, wine, money, time and children. It is for this reason that God required His people to sacrifice a portion of each of these things for His sake.
Animal sacrifices were to be the first and finest of the flocks and herds, crop offerings of grain or wine were also to be from the "firstfruits" of the harvest. A tithe of these things was to be given to support the Levites and priests who served in the worship of God. A portion of money was also to be given each year to provide for the worship of God. One day in seven was reserved for the worship of God. The firstborn males from the flocks and herds were to be given in sacrifice to God. Even the firstborn male child had to be redeemed by a sacrifice and the Levites were considered substitute offerings for the firstborn males of all the other tribes of Israel. The Levites had no inheritance in the land but depended upon the tithes and offerings of the other tribes of Israel as they were dedicated to serving God. All of this was designed to impress upon the minds of God's people that God comes first.
So here is our clue. When we are truly serving God, we "sacrifice" or give up something of lesser value in order to serve the One who is infinitely greater to us than all other things. In a very real sense, we sacrifice everything to Him. As the Isaac Watts says in his hymn, "When I Survey the Wondrous Cross", Were the whole realm of nature mine, that were a present far too small; Love so amazing, so divine, demands my soul, my life, my all.
But in a practical, everyday sense, this plays out in giving up portions of worldly goods or personal pleasures, in service to God. That means we take time for daily prayer, Bible study and worship of God. We also worship regularly with the people of God at least once a week. We give the firstfruits of our income to the cause of Christ, along with special offerings as needs come to our attention. We look for opportunities to lead others to Christ and serve the needs of the poor and those who are suffering. When we serve God rather than ourselves, we are ready to give up anything that stands in the way of serving and pleasing Him. As Isaac Watts also says in that great hymn: All the vain things that charm me most, I sacrifice them to His blood. In other words, the death of Christ on our behalf inspires him to give up stupid, pointless, selfish pleasures in order to serve and please Christ.
When, on the other hand, we serve ourselves, we sacrifice God on the altar of our pleasures. We choose to ignore God, to neglect prayer, to spurn worship, to leave the lost to perish, the poor to languish and the cause of righteousness to fail. We sacrifice God to serve ourselves! In such a state, we are, as the Bible says, "lovers of pleasure rather than lovers of God." (2 Timothy 3:4) It is good for us to see this in such stark terms as it may shock us into repentance. God is truly the greater to whom all lesser goods must bow. Let God be God and we His most willing servants! If this be so, then there will be daily examples in our life of sacrificing lesser goods to serve the greatest good, that is, God Himself.