כִּֽי־כֹ֣ה׀ אָמַ֣ר יְקֹוָ֗ק אַל־תָּבוֹא֙ בֵּ֣ית מַרְזֵ֔חַ וְאַל־תֵּלֵ֣ךְ לִסְפּ֔וֹד וְאַל־תָּנֹ֖ד לָהֶ֑ם כִּֽי־אָסַ֨פְתִּי אֶת־שְׁלוֹמִ֜י מֵאֵ֨ת הָעָ֤ם־הַזֶּה֙ נְאֻם־יְקֹוָ֔ק אֶת־הַחֶ֖סֶד וְאֶת־הָֽרַחֲמִֽים:
לָכֵ֛ן עַתָּ֥ה יִגְל֖וּ בְּרֹ֣אשׁ גֹּלִ֑ים וְסָ֖ר מִרְזַ֥ח סְרוּחִֽים:
The unusual root word מרזח appears only in these two places in TaNa”KH.
This blog is apparently now just quoting from https://net.bible.org/#!bible/Amos+6:3: Religious banquets. This refers to the מַרְזֵחַ (marzeakh), a type of pagan religious banquet popular among the upper class of Israel at this time and apparently associated with mourning. See P. King, Amos, Hosea, Micah, 137-61; J. L. McLaughlin, The “Marzeah” in the Prophetic Literature (VTSup). Scholars debate whether at this banquet the dead were simply remembered or actually venerated in a formal, cultic sense. The book is a full length treatment of the term. (The marzēaḥ in the prophetic literature : references and allusions in light of the extra-biblical evidence. McLaughlin, John L. ; 2001 Leiden ;a Boston : Brill; ISBN: 9004120068)
There are in fact three Doctoral Dissertations on the topic of Marzeah. John McLaughlin’s, 1998: The marzeah institution and rites for the dead: A comparative and systemic study with special attention to the eighth-century prophets
Taek Joo Woo. The marzeah institution and rites for the dead: A comparative and systemic study with special attention to the eighth-century prophets. 1998
David Burton Bryan. TEXTS RELATING TO THE MARZEAH: A STUDY OF AN ANCIENT SEMITIC INSTITUTION. 1973.
Until I read any of these works, I have nothing further to post on the matter.