I think there is a misunderstanding about what it means to "give your life to Jesus". I think the misunderstanding stems from the fact that some are preoccupied with what this means will be lost, and ignore or are blind to what it means will be gained. And this preoccupation results in a resistance to do so. I think this because I know people in all the categories I am about to mention. I was myself in all of them at one time.
Some are resistant to give their life to Jesus because they fear it will mean an intellectual loss. They fear that they will have to concede to a truth that they don't believe to be possible or necessary, and in the process will surrender some amount of their intellectualism or even intelligence.
Some are resistant because they fear it will mean a behavioral loss. They fear they will have to give up or change a behavior or lifestyle that is considered immoral or not in their best interest, but that they believe is either perfectly fine or neutral.
Some are resistant because they fear it will be a literal loss of relationships or possessions. They fear that they will have to break ties with family or friends who don't follow them as they follow Jesus, or they will have to give up literal possessions as they live more sacrificially loving God and others.
Some amount of all this is true as it pertains to what giving your life to Jesus means you will lose. And I could work through that and clarify what is true, and what is more complicated than just an outright "loss" of something. But what I would rather do is fix the preoccupation. I would rather highlight what is to be gained. Large amounts of paper have been filled with explaining what the "loss" of becoming a Christian - giving your life to Jesus - really means; how it is different than you thought, or not as bad as you think, or what. But I don't believe that is the approach of Scripture. In the Word of God, we see the wonder of what is to be gained. And then when we compare the difference, it is worlds apart.
Peter tells us that after we have suffered for a little while, the God of all grace, who has called you to his eternal glory in Christ, will himself restore, confirm, strengthen, and establish you. Because to him be the dominion forever and ever.
First of all - and this is difficult to say - this promise is not for those who are not in Christ, and who have not given their life to Jesus. It is difficult to say because the Bible is so helpful, but for those outside Christ, it is foolishness. And I know people outside Christ, and the only thing that I know will really help them, Scripture, is now to them foolishness. I could quote Scripture all day and without Christ it is likely going to fall on deaf ears, but by the supernatural power of the Holy Spirit (that is a very big but!). Once you give your life to Jesus, the words and truth of Scripture are wonderful and helpful. So in the meantime, trusting the Holy Spirit to illuminate what would otherwise be foolishness, let me help facilitate giving your life to Jesus, or encourage you if you already have.
You have to understand who Jesus is. Then you have to understand what Jesus did, and how it applies to you. Jesus is the image of the invisible God, the firstborn of all creation. For by all things were made, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities, all things were made through him and for him. And he is before all things and in him and all things hold together. Let me say that one again. In him all things hold together. So whatever the "cost" or "loss" of giving your life to Jesus, the gain here is incomparable. It is a fair interpretation to say the implication of this verse is that outside him all things fall apart. So the loss outside Jesus is worst case scenario. And we are still just on who Jesus is. What about what he did?
The saying is trustworthy and deserving of full acceptance, that Christ Jesus came into the world to save sinners (of whom I am the foremost, by the way). Though he was in the form of God, he did not count equality with God something to be grasped, but emptied himself, by taking the form of a servant, being born in the likeness of men. And being found in human form, he humbled himself by becoming obedient to the point of death, even death on a cross. God, the Father, the creator of all, made him, who knew no sin, to be sin on our behalf that we might become the righteousness of God in him. He, Jesus, knew no sin. Yet, God made him to be sin. Why? On our behalf, so that we might have his righteousness - right standing - credited to us as we stand before a holy God who warrants justice and sacrifice for our wickedness. Jesus was put forth as a substitution for us by his blood, to absorb the wrath of God that we deserve.
That is the Jesus who commands you to give your life to him. The Jesus who is the image of the invisible God and in whom and through whom and for him and by whom all things were created and hold together. That Jesus, who came to earth, became like us in every way, yet was without sin, and died on our behalf so that we could share his perfect standing with God because of his sacrifice. And we are preoccupied with what giving our life to this Jesus will cost?! May it never be. What is to be gained is far better.
I think that all people know the authentic attitude of their heart. If you say or even pray that you have given your heart and life to Jesus, but you haven't completely, I think you will know it. We don't need to spend too much time clarifying exactly what it means to give your "whole" life to Jesus. If you haven't yet, you know it. God writes his law on our hearts, so we know. He says that if we seek to gain our life, we will lose it. If after giving our heart to Jesus, there is still some seeking for gain outside Jesus, then it will be clear to us that we have not given our whole heart and our whole life to Jesus. Let's not get bogged down in the grey area. Once you know there isn't a grey area, then it should be clear.
But I know it is not easy to surrender all that you know. I know that is it hard, seemingly impossible, to not be preoccupied with what will be lost. I know that what will, or you think will, be lost is dear to you. I know this because I am a hoarder at heart, just like you. Do you watch the show Hoarders? You should. If for nothing else, you should watch it to check your self. That's what I do. For me, not only is it convicting because without Christ, it is quite possible that I would end up like those people in regards to the amount of physical stuff I would have. Ask my wife. But also, it is generally convicting because I see in my heart the same tendency to hold on to things that seem to make my life more comfortable and familiar, but actually are just more enslaving and disastrous. And the people on that show, like me, are almost completely blind or indifferent about what will be gained if they change their life: more walking space in their house, cleanliness, joy and peace instead of anxiety, etc. They are preoccupied with what they will lose. Not that shirt! Not that old toaster! Let me just keep that old stereo (that doesn't work) and throw away the other one (which actually does)!
So knowing this, I want to encourage you with some of what you will gain by giving your whole life to Jesus, and what you will continue to gain once you have, or if you already have. That is what matters. There is more than this that will be gained. But this is a lot. The God of all grace will restore, confirm, strengthen, and establish you.
Do you need to be restored? Do you have brokenness? Has a relationship, or a situation, or an injustice, or a mistake, or a failure, or a tragedy, led to brokenness in your life? Are you tired of temporary restoration that doesn't prevent more brokenness in the future? Are you tired of pretend restoration that is really just an act as you hide your still present brokenness? Don't you want to be restored? The God of all grace, that is, Jesus, who called us to eternal glory, will restore you. You will gain eternal restoration in Christ. That is worth any loss, is it not?
Do you need to be confirmed? Are you tired of the inconsistent, unfulfilling approvals and confirmation from others? Are you tired of the anxiety of not knowing if you are good enough, or ever will be? Are you ready to be done doubting whether God really loves you or can forgive even your sin? Do want to be confirmed, once and for all, that you are a child of God, and if a child, also an heir? Jesus has caused us to be born again, according to his great mercy, to a living hope through the resurrection of Jesus Christ from the dead, to an inheritance that is imperishable, undefiled, and unfading, kept in heaven for you! Are you ready to give your life to Jesus knowing that ultimately all that it will cost you is perishable, defiled, and fading anyway? Do you want to be confirmed in your standing, and your inheritance that is eternal?
Do you need to be strengthened? Are your physically, mentally, and emotionally tired? Do you have trouble getting up in the morning because your job is either too hard and strenuous, or too boring and seemingly meaningless, and you just can't muster the strength to go? Do you want supernatural energy to face the complexity of that conversation or situation, or intensity of that task? Are you ready to be able to have an eternal perspective in every even mundane and fleeting situation, yet also have the attention and awareness to be where you are every moment? Do you want to be able to run as fast as you used to, or hit a golf ball as far? Wouldn't you rather not have to run or just hit them straight instead of far? (I digress). In Christ, you will be able to do all things through him who strengthens you. All things? Yes! All things that matter. In Christ, you will have the strength to comprehend the breadth, length, height, and depth of the love of Christ - to apply to every situation. God will strengthen you with all power, according to his glorious might, for all endurance and patience with joy.
Do you need to be established? Is there an unfinished nature about everything you do? Do you feel like the accomplishments and efforts in your life are in constant flux and not permanent? Are you tired of constantly working for some status or standing that seems elusive? Are you unsure if you will ever be "presented mature in Christ" and what that will even look like? Are you waiting for a moment or a sign? Are you just waiting to graduate? Will you be established just as soon as you get that job? Or get married? Or have a family? Or once your kids graduate, get a job, or get married, or have kids of their own, who graduate (on so on)? Or once you can retire? Or write that book, or finish that project? Or? Don't you need to be established? The steps of a man are established by the Lord, when he delights in his way; though he fall, he shall not be cast headlong, for the Lord upholds his hand. It is God who establishes us in Christ, and who has also put his seal on us and given us his Spirit in our hearts as a guarantee. In Christ, you will be seen with good order and firmness of faith. If you receive Christ Jesus the Lord, and walk in him, you will be rooted and built up in him - a foundation not like sand that is washed away, but like rock, unmovable - established in the faith.
The teaching, words, and ministry of many people (to be referenced and credited periodically) have contributed significantly to the thoughts and efforts of the writings posted on this site, perhaps in some cases verbatim. May God make me invisible and show me as helpless, show the people quoted and referenced as humble and anointed, and most importantly show Jesus Christ as infinitely glorious and irresistibly desirable.