The only possibility of causing that change in your heart is not having received baptism by immersion and thinking that that is enough to say I am a Christian or to think that attending the services offered by the church is saying going to the services or to carry a bible under your arm or to stick a sticker on the back of the car and that guarantees the fact of being a Christian.
However, being a Christian is much more to be a Christian is to live a life very different from the rest of the people who are not and who cannot understand it either, to be a Christian is to live like Christ every day of our lives here on earth following the example that he he left us living in integrity honesty holiness doing the will of the father in our lives every day.
Proverbs 10: 9
He who walks in integrity walks confidently; But he who takes crooked paths will be found out.
(RNV1960)
That is why I say that being a Christian is accessing a set of principles and values that the world is not willing to practice because it does not know God's purpose for their lives, but the true Christian knows that his life cannot turn to the present things that they dishonor God.
Philippians 4: 8
For the rest, brothers, everything that is true, everything that is worthy, everything that is just, everything that is pure, everything that is kind, everything that is honorable, if there is any virtue or something that deserves praise, meditate on this.
(RVR1960)
To be a Christian is to practice the fruits of the spirit is to be honest, loving integrity, because as a Christian the greatest inheritance that you can leave to future generations is honesty.