also: きゅうかつをじょする
apologize for long neglect of friends
Archaic set phrase used in letters or formal speech to express regret for not having been in touch for a long time.
See also: 久闊を叙する
Writing '久濶を叙す' at the beginning of a letter was a set phrase in old-fashioned correspondence.
Archaic kanji spelling; Cross-referenced with 久闊を叙する as a more common variant.
Variant with 闊 and する; listed as a cross-reference.
The phrase is composed of 久濶 (long interval/neglect) and 叙す (to express/state). The exact historical derivation is uncertain, but it follows classical Chinese-influenced letter-writing conventions.