FOR BURNING INCENSE. But not for a burnt offering, well-being offerings, grain offerings, or libations.

ונתת אותו לפני הפרכת. in the sanctuary.

אשר על ארון העדות, a reference to the curtain dividing the sanctuary from the Holy of Holies.

אחת בשנה, on the Day of Atonement. This was confirmed in Leviticus 16,18 ויצא אל המזבח אשר לפני ה', “he shall go out to the altar that is before Hashem, etc.” On all the other days of the year the golden altar was used only for incense burning.

[THE LORD] SPOKE, etc. When Moshe gathered Israel to separate out the offerings for the Mishkan, he counted them, and this silver was given for the service of the Mishkan, as it is written in [Parashat] Eleh P'kudei (Ex. 38:25), "The silver of the enumeration of the congregation was 100 etc."

TWENTY GEIRAH. It is a kind of coin.

כסף הכפורים, silver intended to atone for the sin of forfeiting one’s life.

על עבודת אהל מועד, as spelled out later in 38,27 where we read מאת אדנים למאת הככר ככר לאדן, “100 sockets totaling 100 talents, 1 talent per socket.

בשמים ראש, valuable fragrances, spices. We know this also from Song of Songs 4,14 עם כל ראשי בשמים. “with all the choice perfumes.” I believe that the word בשמים by itself refers to perfumes and fragrances derived from trees as we also know from Song of Songs 4,16 הפיחי גני ידלו בשמיו, “blow upon my garden that its perfume may spread.” בשמים ראש on the other hand, refers to the sap, or resin from such trees, or to other fragrant plants derived from the soil directly.

מר דרוד, myrrh is globally considered as a valuable source of a fragrance, as is מר עובר, (Song of Songs 5,5) a spice well known and treasured by merchants throughout the world.

ומחציתו, this has been explained in Rashi on Keritut 5

רקח מרקחת, very intensely perfumed.

כל הגוגע בהם יקדש, he must first purify himself as otherwise he would not become consecrated by touching people or utensils who have been anointed with these oils.

ובמתכנתו, corresponding to the proportions of the various ingredients listed here.

ואשר יותן ממנו, from the oil of anointing prepared by Moses.

סמים; we explained this already earlier. (where?)

סמים ולבונה זכה, according to the plain meaning, the Torah first describes the ingredients used for the incense in a general manner, before listing each individually. There follows a description of precisely what was included in the general term סמים. נטף ושחלה וחלבנה, stacte, onycha and galbanum, these are fragrant herbs which I commanded you to use. In addition, you are to take pure frankincense; According to the plain meaning of the text לבונה זכה is not to be counted as one of the spices, fragrances, listed, but the word סמים after the list נטף, שחלה, חלבנה concludes the list of the spices. It is the custom of the Torah to repeat something which had been used as a heading for an introduction when that particular part of the subject has been concluded. We find an example of this in Genesis 9,17 when G’d concluded a covenant with Noach involving the rainbow. He said זאת אות הברית, “this is the sign of the covenant,” both in 9,12, and again in 9,17.

ממולח, thoroughly mixed. The word may reflect the word מלחים, sailors, oarsmen, as these mix and stir the waters which they row.

'ושחקת ממנה וגו, the reason some had to be rubbed into fine particles was that on Yom Kippur the incense was to be of fine particles as we know from Leviticus 16,12 קטורת סמים דקה.