What Does it Mean to "Put Your Faith in Jesus Christ?" and Why You Might Not Actually be a Christian

In studying the testimony of those who have 'deconverted' from Christianity, I've been struck by the importance of something Jesus said--to have eternal life, he said the first step is to "deny" yourself in exchange for a new, supernatural life--a new "you". Yet today there is a trend to not talk about this, or to even affirm the opposite in order to make it as easy as possible for the person to put their "faith" in Christ when, in fact, they have not even taken that first step of faith--laying aside everything they are and cherish, in exchange for what Christ offers. Thus, many people think they are Christians only to be shocked on the day they stand before God and hear him say, "I never knew you."