(24) Very truly I tell you, unless a kernel of wheat falls to the ground and dies, it remains only a single seed. But if it dies, it produces many seeds.
(25) Anyone who loves their life will lose it, while anyone who hates their life in this world will keep it for eternal life.
John 12:24–25, NIV
Dear Father in heaven, we long to be your children and to grow closer and closer to eternal life with all its goodness and truth. In your love to us your children, bless us as we walk on earth under great stress and temptation. Keep us from going astray, and let what you have placed in our hearts grow toward perfection, to your glory and your honor. May our hearts always know the joy that our struggle and suffering are not in vain, that if we are faithful, we may bring forth the fruit of righteousness. Amen.
The context of the words of John 12:24–25, NIV
John 12:20–26 describes a group of Greeks — non-Jewish people who worshipped God — who approach Jesus after the triumphal entry. The disciples appear to be carefully vetting everyone who wants to come near Jesus, knowing that local religious leaders have marked Him for death. Jesus' response indicates that the time has come for His ultimate sacrifice, an event which opens the gospel of grace to the entire world.
Jesus is treated to an honorary dinner at the home of Lazarus, whom He has recently raised from death. At this dinner, Lazarus' sister, Mary, anoints Jesus with expensive oil. Jesus then enters Jerusalem to great fanfare, stoking fears that His popularity will attract the anger of the Roman Empire. That anger even inspires a murder plot against Lazarus. After being approached by non-Jewish seekers, Jesus offers a final plea for people to understand His ministry. In effect, these are the last public words spoken by Jesus in the gospel of John.
Meaning of the words
"Very truly I tell you, unless a kernel of wheat falls to the ground and dies, it remains only a single seed. But if it dies, it produces many seeds"
As He often does when making a bold point, Jesus uses the "Truly, truly" phrase. This comes from a repetition of the word amen, which invokes agreement. Used at the end of a statement—as many do with prayer—it implies agreeing with something already said or believed. Used at the beginning of a remark, as here, implies it's the first-hand original knowledge of the one speaking.
Paul expands on this metaphor of planted seeds in 1 Corinthians 15:36–42. The seed which is planted seems to "die." It sacrifices everything and is lost, so far as it appears. In truth, the seed must be planted in order to become what it was always meant to be. Just as the seed must "lose its life" to fulfill its ultimate purpose, so too does each person need to "lose" their worldly life in order to gain eternity (John 12:25). That doesn't literally mean physical death or martyrdom, but rather the willingness to sacrifice everything in order to follow Christ (Mark 8:35–36).
Jesus will continue to refine this idea in the following verses. That explanation includes a typical ancient-middle-eastern contrast using terms like "love" and "hate."
"Anyone who loves their life will lose it, while anyone who hates their life in this world will keep it for eternal life"
In other passages, Jesus speaks of the fundamental choice between the world and God (Matthew 10:39; Mark 8:35–36). A person cannot cling to worldly things and still make God their top priority. In prior verses, Jesus used the analogy of a seed: it must "die" in order to fulfill its purpose. The symbolism is that of a seed being planted, then growing to maturity. Those who seek to truly follow Christ have to—as it would seem to the world—lose everything. The end result, however, is exactly what the seed—the believer—was always intended for, which is something greater and more glorious (1 Corinthians 15:36–42).
It's important to understand the narrow context of Jesus' words here. The point is not that only those who live in deliberate poverty will be saved. Nor is it that a person must perform the right kind of actions in order to be with God in eternity. Rather, this is a reference to a person's state of mind. This is why Jesus uses the dichotomy of "love" and "hate," with respect to one's earthly life. Just as Jesus was not commanding people to objectively "hate" their family (Luke 14:26), He is not telling us to objectively "hate" our lives. Rather, He's saying that we ought to put 100% of our priority, emphasis, and effort into the will of God. Those who want to cling to the world, instead of Christ, demonstrate that they "love" the world too much to sincerely follow Him (Mark 10:21–23).