As Christians we are called to live lives of holiness. This requires that we honestly check ourselves periodically. But what should we be measuring ourselves against, what standards?
In a school, the principal sets the standards, in order that the pupils know what is expected of them. If they meet the standards, then they will work diligently and in a disciplined manner to produce good grades, which will stand them in good stead for the rest of their lives. While the principal of a school may not himself always live up to the highest standards as an example to the students, in the school of God's kingdom our Principal both teaches the rules and also demonstrates them in his life.
For this reason, we should set our eyes on Jesus and heed all the instructions he gave us in the Scriptures. The Bible is our instruction manual for living a holy life. As we obey it, we are enabled to rid ourselves of the weights that the world loads on us, things like consumerism, popularity, and achievement. Such things cloud our view of God and make it hard for us to walk in the ways of God.
If we walk through the wide gate, we can carry with us a lot that is from the world. However, going through the narrow gate requires us to rid ourselves of the ways of the world, taking little with us apart from the desire to please God and walk in his ways. His ways are challenging, but walking in them will refine our lives.
God's word teaches us how to walk in Gods ways. In each choice we face in life we should ask how much of the world's baggage we are taking with us and how much of Jesus. We may often need to do some repacking, to leave behind those things that will hinder us from leading a holy and pure life. Then we can confidently and joyfully pass through the narrow gate with him alongside us.