Sforno on Exodus 30:35/ספורנו על שמות ל׳:ל״ה

1רקח, each of whom would collect different spices and after mixing them all they would become

2מעשה רוקח, crushed, mixed, etc., a druggist’s handiwork. These various spices did not undergo uniform treatment at the hands of the spicer, druggist..

3ממולח, thoroughly mixed, none of its ingredients remaining identifiable as separate substances.

4טהור. refined to such a degree that it did not contain any foreign substances. The reason why this was of the essence was the fact that the burning up of the incense consisted of burning up the actual spices, derivatives or auxiliaries not being a part of that sacrifice at all. However, with the oil of anointing these extreme precautions did not apply seeing that it was in the nature of the ingredients that auxiliary components were not mixed with it or attached to it before the oil became refined.