One day, when Jesus was saying that God's plan for marriage was for a lifetime, the disciples asked Him why Moses permitted people to divorce their wives easily. Then Jesus clarified that it was because of the hardness of men's hearts (Mt.19:8). Because all of us are born in sin, we have this hardness in our heart as a part of our sinful nature. This nature gives us a tendency to always look out for our selfish interests. It is natural for us to resist anyone or any circumstance that hinders us from doing whatever we want. We may call it a weakness, but actually it is a mark of our old selfish nature which is strong in itself until we crucify it with the power of the Holy Spirit (Ro.8:13). On the other hand, we are very weak when it comes to doing what God wants us to do, which many times involves denying our sinful nature!
Let's look at the narrow gate and the narrow path in this context. The gate that opens to eternal life is small, and the way we have to walk afterwards is narrow. In order to enter through the small gate, we have to make a determination that henceforth we want to do the will of God and not our will, and as we walk along the narrow path we work this out in actual life situations by denying ourselves and doing the will of God.
It is not enough to enter the gate at some point in our life to be sure that we will reach God's destination for us. It is not just about receiving forgiveness for our sins and the promise of a place with Christ. He wants to transform our life to make it more like His in every aspect of character (Ro.8:29). This is the work of the path we have to walk in daily.
When we begin this journey we may be very zealous to follow Jesus with our whole heart. But we soon learn that we did not know the full extent of the hardness of our heart when we started out. Different situations can reveal it to us a little at a time, if we are open to the voice of the Holy Spirit. But even then we may be totally unaware of certain blind spots that we all have. Whenever God has shown me some blind spot in my life, which has corrupted my whole behaviour in a certain way, and I realise how I have been like that all the time without even realising it, I am overwhelmed, in somewhat of a similar way as Isaiah did when he saw the glory of God (Is.6:5). Then I am also struck by the thought that there must be many more such blind spots for me to see still!
When we recognise this reality of the hardness of heart that there is in us, we can begin to stop thinking that we have reached somewhere or accomplished something. There are miles to go... The great apostle Paul, having become so much like Jesus and done so much for Him, thought within himself that there was much ahead towards which he had to run (Php.3:12,13).
This also changes our attitude towards others drastically. We learn to stop looking down on others because of their faults but to respect them wherever they are better than we. Way to go!