It is easy to say the right sort of things to make a good impression. Many do just that. It is the stuff of sales and marketing, job interviews and romantic encounters. Most families adhere to a code of acceptable speech, and so do most groups in society including churches. So we learn how to stay included, by what we say.
 
Jesus probed under the surface of human conversation. How does anyone know what a person is really like? The answer is simple: just listen to them for enough time. When the polished performance has worn off, you will hear what is in their heart, because eventually they will tell you. That is the art of investigative journalism or legal cross-examination. What is stored up in the heart will eventually be verbalised through the mouth.
 
Of course, words are only a part of the 'fruit' of a person's heart: but it is a very important part. Our hearts are like pressurised containers; what we store there, and think about, will become obvious eventually because we will talk about it, good or bad. If that is true here on earth, how much more so when we have to tell the truth to Jesus Christ on the Final Day. We will not be able to manufacture a nice story of our life of service for Him; instead we will have to tell Him everything that is in our hearts. Our eternal destiny will be determined by our own confession, including the reality of our relationship with Him.
 
Jesus was not appealing for a more refined social persona; but for a radical change of heart. However good we pretend to be, we will eventually have to tell the truth to Jesus. If we are to tell Him good things then we need to be changed inside. However religious you are, it applies to you as much as to the religious leaders who first heard these words of Jesus. Those people who are settled that Jesus is their Lord, and are glad of a change of heart (to be more like Him), will be welcomed. The others will not. So let us not be like hypocrites who act out a story which will please their audience. We need changed hearts which will overflow in worship and praise to the Lord.