There are ultimately two ways of life. One is the way of selflessness and outflowing concern for others—that is, the way of love, desiring to give and help. This is the way of God, who is the very embodiment of love (1 John 4:8, 1 John 4:16). His way of life is codified for human beings in His law, which expresses love (Romans 13:10; 1 John 5:3).

Opposed to this is the way of vanity and selfishness—striving to get for oneself. This approach constitutes violation of God's law, which is sin (1 John 3:4). This is the way of Satan, his demons and, following their lead, mankind.

Yet God created human beings to ultimately become members of His family, destined to inherit immortality and live in a harmonious relationship with Him and each other for eternity (Hebrews 2:6-13). To ultimately share eternity with God, we must also share His thoughts, agree with His approach, embrace His way of life and appreciate and uphold His values as expressed by His law (Philippians 2:5-13).

God's written revelation to mankind, the Holy Scriptures, reveals this essential knowledge to us through His laws and teachings (2 Timothy 3:15-17). This forms the basis for the everlasting relationship God desires to have with us. Therefore it is imperative that anyone who seeks this ultimate relationship with God heed the directives of God's law as revealed in His Word.

Within the broad principle of love, Jesus Christ in Matthew 22:37-40 summarized God's law in two great commandments from the Old Testament: "'You shall love the Lord your God with all your heart, with all your soul, and with all your mind [from Deuteronomy 6:5].' This is the first and great commandment. And the second is like it: 'You shall love your neighbor as yourself [from Leviticus 19:18].' On these two commandments hang all the Law and the Prophets."

These two commandments summarize the more specific delineation found in the Ten Commandments (Exodus 20; Deuteronomy 5). The first four of these commandments concern showing love toward God. The last six concern love toward neighbor—one's fellow man. We should understand these commands as summary principles as well, rather than limiting each to the strict wording in the verses where they are listed.

Part of Jesus' purpose in coming to earth was to "magnify the law" (Isaiah 42:21, King James Version). An important way He did this was by showing the full spiritual intent of God's commandments—both through His teachings and through His perfect example of obedience.

In His teaching, Jesus explained that God's commandments apply well beyond the mere letter. They are to regulate even our thoughts. For instance, He explained that unjust rage against someone is breaking God's Sixth Commandment against murder and that lusting after a person not one's spouse is committing adultery in the heart, constituting a violation of the Seventh Commandment (Matthew 5:21-28).

God requires that we obey the spirit of each of the Ten Commandments. Starting with the first four on love toward God, the First Commandment against not worshipping other gods also means that we are not to allow anything to come before God in our lives.

The Second Commandment forbids worshipping before physical representations of God, like statues or pictures of Christ, but it also prohibits limiting God with a false image in one's mind.

The Third Commandment says we are not to take God's name in vain, which means we must be quite careful in how we use it, but also that we must not dishonor God's reputation by how we live.

The Fourth Commandment, about keeping the Sabbath holy and not working on it, also includes the principle of structuring our workweek around it and maintaining a spiritual focus throughout the day. 

Moving to the last six of the Ten Commandments on loving our neighbor, the Fifth Commandment tells us to honor our parents, which includes obeying them when young, respecting their wisdom when we are adults, caring for them when they are old and not bringing shame on one's family name. (Implicit in this command is also the need for parents to be honorable.)

The Sixth Commandment, as already mentioned, prohibits murder. In the letter this means not usurping God's prerogative in taking human life (as only He has the authority to do so or to command that someone else do so). We are not to murder self or help someone else to commit suicide, and we are not to commit abortion. In the spirit of the law, we are not to hate or devalue another person.

The Seventh Commandment, forbidding adultery, in its spiritual intent prohibits any sexual relations outside of marriage, as well as fantasizing about such relations. Thus sexual immorality in general, including premarital sex and homosexual relations, is forbidden, as detailed elsewhere in God's laws.

The Eighth Commandment, prohibiting stealing, in the spirit includes safeguarding what belongs to others and seeking honest gain in order to even share with others in need.

The Ninth Commandment, forbidding the bearing of false witness against one's neighbor, in its full intent includes protecting the reputation of others and maintaining complete honesty and integrity in all dealings—always telling the truth.

And finally, the Tenth Commandment, prohibiting coveting what belongs to a neighbor, is, even as expressed in the letter, a spiritual commandment about thoughts in one's mind. We must refrain from lusting after what we cannot lawfully obtain.

These commandments are further supported and clarified by other laws and instructions in Scripture. In fact, the entire Bible serves as God's revealed law to us, telling us what He requires. Yet sadly, man rejected God's law at the very outset of human history.

Sin, the transgression of the law, was introduced to humanity in the Garden of Eden. Satan lied to Adam and Eve concerning the tree of the knowledge of good and evil (Genesis 3:4; John 8:44). Contrary to His deceptive prediction, the first man and woman did die. As their descendants, we all share the common condition of mortality (Hebrews 9:27).

It's no coincidence that sin's universal presence in all human beings (Romans 3:23) is connected to death and the withholding of God's gift, eternal life (Romans 6:23).

The pervasive nature of sin and death is demonstrated by the human tendency to disregard and disobey God's law (Romans 8:7). Self-deception frequently accompanies this departure from God's perfect guidelines (Jeremiah 17:9; Jeremiah 10:23). The influence of Satan is unmistakable in this pattern, both directly (Ephesians 2:1-3) and indirectly through those he deceives (2 Corinthians 11:13-15).

Having become the adversary of God through his own rebellion, Satan has covertly enlisted the human race in his battle. Sinful human beings become enemies of God since all sin, in addition to its effect on other people, is by definition against God (Genesis 39:9; Psalm 51:4).

Violating any of God's instructions is sin (1 John 5:17), but it is also sinful to omit doing what one should do (James 4:17) or to violate one's conscience (Romans 14:23). Furthermore, sin is an enslaving power from which we need redemption and release (Romans 7:23-25). We are powerless to bring about this redemption on our own (1 Peter 1:18-19).

Since sin in any form brings about alienation from God (Isaiah 59:1-3; Ephesians 4:17-19) and eventual death, no amount of obedience following such conduct can reverse its effect, even though obedience is expected. Only the perfect sacrifice of Jesus Christ can procure our release (Hebrews 2:14-15) and reconcile us to God. 

Through forgiveness of sin, available by God's grace (Romans 3:24), a Christian finds freedom in obeying God's law (James 1:21-25). Rather than being enslaved to sin by disobedience, we serve God by obedience and walk the path He intends, to be led to eternal life in His Kingdom by His generous and undeserved gift (Romans 6:16-23).

To return to a former life of sin is a serious matter in the sight of God (2 Peter 2:20-22). However, the only sin that cannot be forgiven is the fully informed, willful refusal to repent, utterly rejecting God and the sacrifice of Jesus Christ, by which forgiveness of sin is made possible (Hebrews 6:4-6; Hebrews 10:26-31).

This sin is described by Christ as "blasphemy against the Spirit" (Matthew 12:31), a knowing outright rejection of the power and authority of God. After every human being has had a full opportunity for salvation, those still unrepentant will be destroyed (Revelation 20:14-15), thus fulfilling the ultimate penalty of sin, the second death. (See the chapter titled The Resurrections and Eternal Judgment.)

Although every person is responsible for his own sin (Ezekiel 18:4; Ezekiel 18:20), Satan the devil is identified as the tempter, the deceiver of mankind and the one ultimately responsible for leading humanity into sin (Matthew 4:3; 1 Thessalonians 3:5; Revelation 12:9; Revelation 20:1-3).