Shutting the door

Do not give what is holy to dogs,
and do not throw your pearls before swine

I will shut the door 
in the face of the uninvited.
I will block the way of rapid dogs and ravenous pigs.
I uproot weeds. I cut out cancers. 
I avoid infections.

We have choices in our lives. 
We can pick and choose 
what we allow to enter. 

Only the foolish or insane 
would try to enter a door 
forever barred against them.

(What is right and good is greater than DNA - take the hint)