The 144th mitzvah is that we are commanded to separate the first of our shearings and give them to a kohen.

The source of this commandment is G‑d's statement,1 "You shall give him the first of your shearing."

This mitzvah applies only in Eretz Yisroel.

The details of this mitzvah are explained in the 11th chapter of tractate Chullin.