This Bible contradiction is from the Skeptic's Annotated Bible.
Matthew 19:12 View context
For there are some eunuchs, which were so born from [their] mother's womb: and there are some eunuchs, which were made eunuchs of men: and there be eunuchs, which have made themselves eunuchs for the kingdom of heaven's sake. He that is able to receive [it], let him receive [it].
Deuteronomy 23:1 View context
He that is wounded in the stones, or hath his privy member cut off, shall not enter into the congregation of the LORD.