In this great pastoral letter, Paul gives practical advice to Timothy. Here he uses his own life as an example of how to live for Jesus. And he goes on to say that anyone living for Christ shall be attacked. Things don't change much over the years.
The main lesson Paul gives today is when he says that the scriptures are inspired by God and can be used as a defense of the faith. Scripture can also be used as a guide for life and as a way to get to know Jesus. This is why it is so important to read, study and meditate upon the Word of God, both as Jesus and as the written word. We can never exhaust the meaning of the written word, just as we can never exhaust the meaning of the Word. If we think that we can never understand all - we are right. But even a small glimmer of understanding of a being such as God is worth the effort of study!