Two of the most important passages in all of Scripture, not precisely because of what they say, but because of what happened between each passage so that the latter can say what it says:

Deuteronomy 23:1, “No one whose testicles are crushed or whose male organ is cut off shall enter the assembly of the Lord.

Isaiah 56:3–5:

3 Let not the foreigner who has joined himself to the Lord say,
“The Lord will surely separate me from his people”;
and let not the eunuch say,
“Behold, I am a dry tree.”
4 For thus says the Lord:
“To the eunuchs who keep my Sabbaths,
who choose the things that please me
and hold fast my covenant,
5 I will give in my house and within my walls
a monument and a name
better than sons and daughters;
I will give them an everlasting name
that shall not be cut off.”