Christian ethics: Whoever says, ´I know him,´ but does not do what he commands is a liar. 1 John 2:4

The apostle John in his first letter addressed to the churches of Asia taught about the importance of Christian ethics. While Jesus summarized this ethic in the Sermon on the Mount with the Beatitudes (Matthew 5:1-12, Luke 6:20-26), the apostle John with devotion placed the fulfillment of the word of God and the knowledge of the truth from the perspective of the commandments: "If we obey God's commands, then we are sure that we know him" 1 John 2:3.
The doctrine of the Kingdom of God, the dominion, government, or empire of God's perfections, expounded by Jesus is fundamentally a continuation of the sapiential literature of the wise men of Israel, such as Solomon, David, or Ben Sira; wisdom as a universal good of humanity is a fact and Lord Jesus never ignored this issue. This is why, although Jesus spoke of a new commandment, the commandment of charity ("Love your neighbor as yourself" Mark 12:31), the commandments announced in the Old Testament do not lose their validity in the Christian teaching: "Fear God and keep his commandments, for this is the whole duty of man", Ecclesiastes 12:13.
And this was demonstrated when Jesus met a rich young man who, moved by curiosity and not by the fear of God (constancy, firmness, devotion, equanimity, and stability), approached the divine master to ask him how to inherit the spiritual gift of eternal life. This question was very important for Jesus because the eternal life or the immortality was considered in ancient times a mystical secret only within reach of a few teachers, a knowledge that Alexander the Great also sought when he conquered the ancient world. And Jesus, in response to this question, asked him if he had fulfilled the main commandments, and the rich young man answered yes, and then Jesus told him that only the fear of God remained for him, and since this man loved riches he rejected Jesus and his teachings.
This is why the apostle John in his first epistle taught that whoever rejects the wisdom of the Old Testament also rejects Jesus: "Whoever says, ´I know him,´ but does not do what he commands is a liar" 1 John 2:4. Ultimately, what John taught is that the Kingdom of God is a coherence between what is taught and what is lived.

For more information visit my profile follow the link and download for free my ebook.