What does John 12:26 mean?

Jesus is speaking in front of a group of non-Jewish seekers, who have come to see Him in Jerusalem (John 12:20–22). The main message He is giving deals with the need for a person to "die" to themselves in order to "live" in eternal life. This is not a question of earning one's salvation—rather, it's a measure of a person's sincerity. Those who earnestly want to submit to God will put Him at the very top of their priorities. They won't "love" things as much as they "love" God and His will. To the world, that looks like death, just as burying a seed has all the appearance of killing it (John 12:24). In reality, that act is what allows the seed to achieve the purpose for which it was created!

In the same way, being a born-again believer in Jesus Christ means "dying" to one's self and self-interests (1 Corinthians 15:36–42; Romans 6:6–8). Those who resist that obedience are like a seed which is never planted; seeming to "live" but merely stagnating in a state of immaturity and barrenness (Mark 10:21–23).

Jesus' upcoming words are a continuation of this speech, which includes a supernatural response from heaven. In keeping with Jesus' teachings about those who will or will not hear His voice (John 10:26–27), most of those who hear this divine answer will dismiss it as something natural and meaningless (John 12:27–29).