1 John 3:13 would read in today’s vernacular, “Therefore, brothers and sisters if and let us assume that it is true for the sake of argument that the world does at any time hate any one of you and we agree that they do hate all of you, then each one of you must continue to make it your habit of not being taken by surprise.”
First John 3:13 presents the result of the previous assertions of verses 11-12. In verse 12, John asserts that they were taught from the beginning that they must continue to make it their habit to love each other. Then, in verse 12, he says that they were by no means to conduct themselves like Cain who murdered his brother. He, then, asks a rhetorical question which asks why Cain did this. John answers it by pointing out that Cain’s actions were evil but his brother Abel’s were righteous. The consequence of the murder, according to verse 13, is that the ungodly people of the world under the rule of Satan will hate the believer who practices righteousness by obeying the command to love one another. As is true of 1 John 2:15, “the world” here in 1 John 3:13 is the noun kosmos which is the primary word in the Greek New Testament for the world. It is the orderly arrangement of the material life. Our word “cosmetics” comes from this word. The three main uses in the New Testament is (1) the orderly arrangement of the heavens and earth as created by God. (2) The cosmos (Greek, kosmos) may also refer to the world in its arrangement of the inhabitants of the earth in tribes and nations or peoples (Acts 17:26; John 3:16; 1 Corinthians 4:9; 1 John 2:2; 2 Peter 2:5). (3) But most importantly, kosmos is used of a vast system and arrangement of human affairs, earthly goods, godless governments, conflicts, riches, pleasures, culture, education, world religions, the cults and the occult dominated and negatively affected by Satan who is god of this satanic cosmos. This system tempts the people of God, while masquerading as an angel of light.
Therefore, “the world” in 1 John 2:15 and 3:11 describes the systematic arrangement of human affairs, earthly goods, godless governments, conflicts, riches, pleasures, culture, education, and world religions. It not just a system. It is an organization, which by its very nature implies that it is formed into interdependent parts for united action.
Finally, John states that each of them must continue to make it their habit of not being taken by surprise. The world will always hate the believer but at times they will do so for the practice of divine righteousness in their lives. John is not teaching in 1 John 3:13 that the world will “always” hate the believer, but at times they will hate the believer for the practice of divine righteousness in their lives. This exposes the sinfulness of the people enslaved to Satan, then they must expect to be rejected by these sinful people. Furthermore, if the believer interferes with the evil practices of unregenerate people, which Jesus did in the temple, they must expect suffering and even death (cf. John 15:18-19, 25; 17:14). This echoes the teaching of Jesus in John 15:18-25 and 17:12. He warned His disciples that they would be hated by the people of this world system and organization. It would hate them because it hated him first and because they were associated with Him. Hating Jesus is hating the Father who sent Him. The apostle John is teaching in 1 John 3:13 that the world hates God and the children of God.