Translate this the way your language emphasizes that what follows is important and true. See how you translated "Truly, truly" in [John 1:51](../01/51.md).
Here "a grain of wheat" or "seed" is a metaphor for Jesus's death, burial and resurrection. Just as a seed is planted and grows again into a plant that will bear much fruit, so will many people trust in Jesus after he is killed, buried, and raised back to life. (See: [[rc://en/ta/man/translate/figs-metaphor]])