Alright this chapter has alot of info in it so I hope I don't loose anyone.
Chapter 2: 1-6 Christ is our Advocate (helper, comforter, called alongside)
In John's opening statement when he refers to little children he is not really talking to a group of kids but rather is showing a sincere side or concern for the people. He keeps mentioning the word sin throughout the passage and this I believe is more geared towards the "acts" of sin than someone having a sinful lifestyle. Because Christ is our Advocate He then steps in and completes us. We ourselves will never be perfect and that is why through Christ and only Him we are able to have eternity with God. In verse 4 it begins to talks about "His Commandments." This isn't referring to the 10 Commandments that God gave Moses but instead it talking about the passage John 13:35 that commands us to love and then also in Matthew 28:19-20 where we are to share His Word (bear witness to Him).
Chapter 2: 7-11 In verse 7 it is stated that he is not writing a new commandment but an old one that they already knew about. This is talking about how usually the first thing most Christians learn first is to love. Not only God but your neighbor as well. Look at Deut. 6:5 and Lev. 19:18. John also writes about a new commandment as well seen in John 13:34, "A new commandment I give to you, that you love one one another; even as I have loved you, that you also love one another." John continues to say later on in the passage that if we hate our brother that we are in darkness and does not know what he is doing. Hate =self-destruction.
Chapter 2: 12-17 In verse 12 it mentions little children again like in the opening but this time it is not determined if it is referring to actual children or the beginning stage of Christianity. There are three levels that are talked about each illustrates a different level of knowledge or strength. The "children" know that there is a God and that they are forgiven, the "fathers" are mature in their knowledge, and the young men are strong and have overcome struggles. You will have to read these verses closely to see which area you believe John is talking about. In 15 it states that we are not to love the world. This isn't talking about not loving the people in the world but not to love any opposition against God. Read Romans 8: 19-20-23 to better understand what John is talking about when he says the world will pass away. The earth awaits purification and renewal.
Chapter 2:18-23 In this part of the Scripture John writes about the last hour is near. He truly thought that the Lord would return during his lifetime. We have to remember that John was an eyewitness to all the things Jesus did during his ministry. Not only was Jesus His teacher but He was also his close friend. Why wouldn't John not want Jesus to return soon. The big topic in this group of verses is the appearance of the Antichrist (against Christ). Yes one day there will be a main Antichrist that will come but this is not what John is referring to. He is stating that the Gnostic teachers were all around them then and they were denying Christ and God of their power. He is asking the people to acknowledge that these teachers are spreading lies and are not of truth.
Chapter 2:24-29 When we are anointed by Him, He will teach us all the things that are truth we need. When we learn these things we then need to follow what He says. This will give us boldness and we won't back away when He returns. By knowing these things we will recognize righteousness in others and know that they are also believers in Him.
* As Christian we need to be on constant alert that we are not letting false teachers fill our minds and hearts with wrong doctrine. If you question something you hear from someone, please take the time to sit down and research it in the Scriptures for yourself.