The root KPR is attested in the Akk. base stem KAPARU, meaning wipe
off, smear on... and in the so-called D. stem KUPPURU, meaning wipe
off, clean, rub, ritually purify; Akk. also has it in the N stem =
Heb. ni... In Arab. the situation is more similar to Akk. than has
generally been recognized... The base stem KAFARA means cover,
conceal, deny, disbelive, be ungrateful... and the D stem KAFFARA
means conceal, annul, expiate, do penance... More extensive summaries
of the root KPR in the Sem. languages can be found in Levine,
PRESENCE, 121-27, and esp. Janowski, 29-102...
References are:
WA VanGemeren, "New International Dictionary of Old Testament Theology
and Exegesis", vol.2, Zondervan 1997
BA Levine, "In the Presence of the Lord", SJLA, 1974, 55-77
B Janowski, "Suehne als Heilsgeschehen...", WMANT 55, 1982