33 Heb “he made darkness his hiding place around him, his covering.” 2 Sam 22:12 reads, “he made darkness around him coverings,” omitting “his hiding place” and pluralizing “covering.” Ps 18:11 may include a conflation of synonyms (“his hiding place” and “his covering”) or 2 Sam 22:12 may be the result of haplography/homoioarcton. Note that three successive words in Ps 18:11 begin with the Hebrew letter samek: סִתְרוֹ סְבִיבוֹתָיו סֻכָּתוֹ (sitro sévivotayv sukkato).
34 Heb “darkness of water, clouds of clouds.” The noun “darkness” (חֶשְׁכַת, kheshkhat) is probably a corruption of an original reading חשׁרת, a form that is preserved in 2 Sam 22:12. The latter is a construct form of חַשְׁרָה (khashrah, “sieve”) which occurs only here in the OT. A cognate Ugaritic noun means “sieve,” and a related verb חָשַׁר (khashar, “to sift”) is attested in postbiblical Hebrew and Aramaic. The phrase חַשְׁרַת מַיִם (khashrat mayim) means literally “a sieve of water.” It pictures the rain clouds as a sieve through which the rain falls to the ground (see F. M. Cross and D. N. Freedman, Studies in Ancient Yahwistic Poetry [], 146, n. 33).