כִּֽי־תְמ֣וֹל אֲ֭נַחְנוּ וְלֹ֣א נֵדָ֑ע כִּ֤י צֵ֖ל יָמֵ֣ינוּ עֲלֵי־אָֽרֶץ׃
(우리는 어제부터 있었을 뿐이라 지식이 망매하니 세상에 있는 날이 그림자와 같으니라)
Malbim
And as regards his [Eliphaz's] hint of a world of resurrection, as he said, so as to prevent them perishing for ever (Job 4:20), Job rejects this. For just as he denies Providence and free-will and attributes everything to the governance of nature and astrology, so he denies resurrection and future reward. As the Talmudic Sages said (Baba Batra 16b): 'Job denied the resurrection of the dead' (Ch. 7:8-9).
Siftei Chakhamim
As you had been doing till now. I.e., [ כתמול שלשום does not refer to] just the past two days. כתמול here means the same as in (Iyov 8:9), “We have been since תמול (yesterday) so we do not know,” [where it is to be understood figuratively]. Consequently, the word שלשום (“and the day before”) is unnecessary—since תמול includes everything in the past. Nevertheless, it says שלשום so we will not mistakenly think that this תמול follows its usual, [i.e., literal] meaning in Scripture.