Did Armstrong's teachings on Sabbath and festivals influence any modern denominations?
Executive summary
Herbert W. Armstrong taught Saturday Sabbath observance, Levitical dietary rules and the seven Mosaic “Festivals of God,” and the Worldwide Church of God (WCG) institutionalized those practices [1] [2]. After Armstrong’s death the movement fractured: the main WCG formally abandoned many Armstrong doctrines in the 1990s while multiple splinter groups continue to practice his Sabbath and festival teachings [3] [4].
1. Armstrong’s specific teachings on Sabbath and festivals — a short primer
Herbert Armstrong concluded that the Mosaic law had not been “done away,” insisted on Saturday (seventh‑day) Sabbath observance, promoted Levitical dietary laws, and taught observance of seven annual festivals — Passover, Unleavened Bread, Pentecost, Trumpets, Atonement, Tabernacles and the Last Great Day — which the WCG treated as days of worship [1] [5] [2].
2. Institutional adoption: WCG made Sabbath and festivals central
The Worldwide Church of God under Armstrong required Sabbath keeping and annual feast observance as core practices, even tying finances and organizational life to festival observance (tripling tithes for Feast of Tabernacles is one historical example in WCG reporting) [2] [6]. Contemporary reference works and church histories document the centrality of these practices in Armstrong’s organization [1] [2].
3. Post‑Armstrong realignment: mainstream WCG moved away
Following Armstrong’s death, successive WCG leaders (notably the Tkach era) dismantled many unique Armstrong doctrines and moved the organization toward mainstream Protestant orthodoxy, opening doors to other churches and abandoning the more distinctive legal observances [3]. Reports note that WCG leadership “jettisoned” much of Herbert Armstrong’s teachings even as the church wrestled with its legacy [3].
4. Splinter denominations kept Armstrong’s Sabbath and festival practices
Available sources identify multiple splinter groups and organizations that continue to identify with “Armstrongism” and its distinctive practices; Wikipedia and apologetics summaries list offshoots and note that many hold to Armstrong’s Sabbath and feast observances [4] [7]. Study documents and secondary accounts also describe how Armstrong’s festival teaching influenced later Church of God branches that preserved those customs [5] [8].
5. How historians and critics frame that influence
Encyclopedias and academic summaries treat Armstrong’s upholding of Sabbath and festivals as a defining, controversial feature of his movement — one that set the WCG apart from mainstream Christianity and that critics used to label the movement heterodox or “cult‑like” [2] [9]. Archive materials from related Church of God bodies show internal debates as Armstrong promoted Hebrew festivals to national ministerial bodies [8].
6. Competing perspectives and ongoing debate
Some observers emphasize continuity — that Armstrong’s Sabbath and feast teachings persist today in splinter groups that self‑identify with his legacy [4] [5]. Others emphasize discontinuity — that the largest surviving organization that descended from WCG intentionally repudiated those distinctives and integrated with broader Christian denominations [3]. Both perspectives are present in the sources cited.
7. Limitations in current reporting and open questions
The provided sources document Armstrong’s doctrines and note the existence of splinter groups but do not provide a definitive list quantifying how many modern denominations practice his Sabbath/festival teachings or detailed case studies of particular contemporary churches’ liturgies (available sources do not mention a comprehensive, dated roster of denominations still using Armstrong’s calendar). Detailed membership figures and current worship calendars for every splinter group are not found in these sources (available sources do not mention up‑to‑date membership counts tied to festival observance).
8. Bottom line for the reader
Armstrong’s teachings directly shaped the WCG’s Sabbath and festival practice, and that model continues in multiple splinter groups that self‑identify as heirs of “Armstrongism”; meanwhile the principal descendant body publicly renounced many of Armstrong’s distinctives and moved toward mainstream Christianity [1] [3] [4]. If you want a firm roster of modern denominations that still follow his festival calendar, additional primary research of individual splinter churches and their current statements of belief is required — this set of sources documents influence and fragmentation but not a complete, contemporary catalog (available sources do not mention a complete contemporary catalog).