Or HaChaim on Numbers 8:3/אור החיים על במדבר ח׳:ג׳

1 ויעש כן אהרון, Aaron did so, etc. Why did the Torah have to write again אל מול פני המנורה, seeing this was already implied in the words: "Aaron did so?" The words: as G'd had commanded," are also superfluous as they are part of the line "Aaron did so." Perhaps we can explain this as follows: The words ויעש כן refer to the dismantling of the candlestick, i.e. the removal of its lamps. The Torah added the words כאשר צוה ה׳, to tell us that he cleaned the lamps so that the whole candlestick should be as new. This would justify what the Midrash had called the inaugural aspect of the cleaning of the candlestick. The reason the Torah adds the words אל מול פני המנורה is to tell us that Aaron kept to the sequence as he had been instructed, i.e. that the cleaning proceeded towards the centre lamp and not from right to left or from left to right. [Compare Yuma 33 for a full discussion of that procedure. Ed.] The reason the Torah wrote כאשר צוה, was to inform us that contrary to the fact that Aaron had received G'd's command during the daylight hours so that I might have expected him to carry it out during daylight hours, he did so at the time concerning which G'd commanded it, i.e. in the evening. Although we have said that the נר מערבי was lit by day, on occasion, this occurred rarely and always signified that Israel was out of favour, else that light would not have gone out prematurely. As long as Aaron was alive this never happened. The words also imply a compliment for Aaron. Whatever Aaron did he did not do in order to be viewed as distinguished but he did so purely in order to fulfil G'd's command.