“And the beginning of the shearing of your flock you shall give to him!” (Devarim 18:4)
It is a positive commandment to give the beginning of the shearing of the flock to the Priests, and about this it says “And the beginning of the shearing of your flock you shall give to him!”. The procedure for this commandment is that anyone who has at least five sheep, whether male or female, lambs or big sheep, and even if he had sheared them many times, is obligated to give the first shearing as a present to the Priest each time he shears. This present has no biblical fixed amount, but Chazal said that he should give a sixtieth.
Amongst the roots of this commandment are that since the Priests who are constantly serving Hashem have no portion in the land or in the shearing, Hashem supplied them with all of their needs through their brothers, and he gave them Terumah and Terumas Ma’aser as their bread and wine, and the portions of the animals (foreleg, cheeks and stomach) and their portion in the offerings in the temple so that they would have enough meat, and besides for that they need clothing and for this purpose Hashem gave them the first of the shearing for their clothing. He also gave them the “purchased field”, “theft from a convert”, the “Charamim”, “Redemption of the firstborn”, for other expenses and necessities which a person needs.
Amongst the laws of this commandment are that there is only an obligation to fulfil this commandment with wool which is soft and can be used for clothes, but if the wool is hard and unfit for clothing it is exempt from this commandment. If the wool is red, black or brown, he is nevertheless obligated to fulfil this commandment, as is fit for clothes.
This commandment applies to men and to women, to Yisraelim and Levites, whether the temple is standing or not. It only applies in Eretz Yisrael, and not elsewhere. One who has the correct shearing, and does not give some to the Priest, has transgressed this commandment.