Matthew 23:31-35

Wherefore ye bear a testimony to yourselves, that ye are the children of those who killed the prophets.

Luke 11:50-51

that the blood of all the prophets, which hath been shed since the foundation of the world, may be required of this generation:

Treasury of Scripture Knowledge

Summary

So ye shall not pollute the land wherein ye are: for blood it defileth the land: and the land cannot be cleansed of the blood that is shed therein, but by the blood of him that shed it.

Bible References

It defileth

Matthew 23:31
Wherefore ye bear a testimony to yourselves, that ye are the children of those who killed the prophets.
Luke 11:50
that the blood of all the prophets, which hath been shed since the foundation of the world, may be required of this generation: