What is TWOT?
Theological Wordbook of the Old Testament

The essential reference for understanding Hebrew words at their theological root — and how BiblicalTools.org puts it at your fingertips.

The Book Behind the Numbers

The Theological Wordbook of the Old Testament (TWOT) is a two-volume reference compiled by R. Laird Harris, Gleason L. Archer Jr., and Bruce K. Waltke — three of the most respected Old Testament scholars of the twentieth century. First published in 1980, TWOT assigns a unique number to every Hebrew and Aramaic root in the Old Testament and provides a concise theological discussion of each word family.

Where a concordance tells you where a word appears and a lexicon tells you what it means, TWOT tells you why it matters theologically. It traces how a single root unfolds across the narrative of Scripture — from Genesis to Malachi — revealing connections you would never see in translation alone.

TWOT Numbers vs. Strong's Numbers

Most Bible students are familiar with Strong's Concordance numbers (H1–H8674 for Hebrew). Strong's indexes every distinct word form in the Hebrew text. TWOT takes a different approach: it groups related words under their shared root.

For example, Strong's assigns separate numbers to the noun, verb, and adjective forms derived from a single Hebrew root. TWOT gathers them under one root number and uses letter suffixes (a, b, c…) for each derivative. This root-based system reveals word families and semantic connections that Strong's numbering obscures.

The result: TWOT is a theological tool, while Strong's is a concordance tool. Serious word study uses both.

Example: חֶסֶד — "Chesed"

חֶסֶד
Transliteration
chesed
Strong's Number
H2617
TWOT Number
698a
Meaning Range
Lovingkindness, covenant loyalty, steadfast love, mercy, faithfulness
Root (TWOT 698)
חָסַד — to show covenant faithfulness

In the BiblicalTools.org Bible Reader, clicking the word chesed in any Old Testament passage surfaces both its Strong's number (H2617) and its TWOT number (698a). The TWOT entry reveals that this word does not simply mean "kindness" — it carries the weight of covenant obligation, the loyal love Jehovah pledges to His people. Understanding the root (TWOT 698) connects chesed to every other word in its family, deepening your study exponentially.

TWOT in the BiblicalTools.org Bible Reader

Our interlinear Bible reader integrates TWOT numbers directly into the Hebrew text. Every word is linked to its root entry, so you can move from reading a passage to studying the theological depth of its vocabulary in one click. No separate books, no cross-referencing between volumes — the data is embedded in the text.

  • Click any Hebrew word to see its Strong's number, TWOT number, transliteration, and gloss
  • Explore root connections — see every word derived from the same root
  • Read alongside the KJ3 Literal Translation — the most literal English rendering available
  • No Hebrew knowledge required — everything is presented visually with English equivalents
Try the Bible Reader with TWOT Integration

Frequently Asked Questions

What is TWOT?
TWOT stands for the Theological Wordbook of the Old Testament, a two-volume reference by R. Laird Harris, Gleason L. Archer Jr., and Bruce K. Waltke. It assigns a unique number to each Hebrew root word and provides a theological analysis of how that word and its derivatives are used across the entire Old Testament.
How are TWOT numbers different from Strong's numbers?
Strong's numbers index every distinct Hebrew word form individually. TWOT numbers group related words under their shared root, using letter suffixes for derivatives. TWOT focuses on theological meaning and semantic range, making it a deeper tool for studying how words function within Scripture's larger story.
How does BiblicalTools.org use TWOT?
The BiblicalTools.org interlinear Bible reader displays TWOT numbers alongside Strong's numbers for every Hebrew word. Clicking a word reveals its TWOT entry, root connections, and theological significance, allowing you to study Hebrew word meanings directly within the text — no separate reference books needed.
Do I need to know Hebrew to use TWOT?
No. TWOT was designed for pastors, students, and serious Bible readers without formal Hebrew training. The interlinear reader on BiblicalTools.org presents everything visually — transliterations, glosses, and root connections — so you can study Hebrew word meanings without knowing the language.