the footstool of a throne: the low rest where an enthroned king sets his feet, used in Scripture only as an image of God's royal presence and rule
TranslatabilityApproximateCertaintySettled
This word never names a plain piece of household furniture. It appears only six times, and every time it is joined to the word for "feet" and points to a throne (כִּסֵּא). Behind it stands a picture common across the ancient world: a great king seated high, with a footstool beneath him. Scripture takes that picture and gives the throne to God, whose seat is imagined above the ark or in heaven itself, so the footstool becomes the place where his feet come to rest.
Across its six uses the footstool grows outward.
In the worship songs it is the sanctuary, the ark and the temple mount, the one spot on earth where the unseen King rests his feet and where his people bow low.
In Isaiah the image widens to its limit: the whole earth is his footstool, so no building could ever contain him.
In Lamentations that same footstool becomes a place of grief, the holy site God will not even bring himself to remember in the day of his anger.
One use turns the image in a different direction. In Psalm 110 the footstool is not a place of worship but the enemies of God's chosen king, laid low beneath his feet in total defeat. This is the line the New Testament quotes more than any other verse of the Old Testament, applying it to Jesus reigning at God's right hand until every enemy is put under his feet.
Nuances
1athe place where God rests his feet: the ark, the temple, or Zion, toward which worshippers bow down
1Ch 28:2*Psa 99:5Psa 132:7Lam 2:1
1Ch 28:2
What "the footstool of the feet of our God" refers to in this verse: the ark of the covenant itself, or the temple as a whole that houses the ark.
contestedThe temple as a whole is the footstool, with the ark simply placed inside it, a usage distinctive to Chronicles rather than preserved archaic language.; Japhet, I & II Chronicles (OTL), 486-488
contestedThe ark and its footstool stand in tight coordination, continuing older Zion-cult footstool language echoed from Psalm 132.; Klein, 1 Chronicles (Hermeneia), ad loc.; Knoppers, 1 Chronicles 10-29 (Anchor Bible 12A), 918ff.
1bthe earth itself as the rest for God's feet, with heaven as his throne
Isa 66:1
1cdefeated enemies placed under the feet of a victorious king, an image of complete conquest
TranslatabilityDirect
Psa 110:1
Disputed
Whether the footstool image is at heart one of subjugation (something trampled underfoot) or of royal repose (a resting-place for the feet). The choice colors the mood of the worship passages.
minorityThe word comes from a root meaning to trample or overthrow, so the footstool is fundamentally an implement of subjugation.; BDB, s.v. הֲדֹם; TWOT, entry 475a
majorityThe word means simply a place of rest for the feet, drawn from shared Late Bronze Age royal furniture, with no inherent sense of trampling.; Fabry, TDOT 3:325; Cornelius, NIDOTTE 1:1011-1012
always the footstool of a divine or royal throne, tied to God's enthronement and paired with the word for feetPsa 99:5
Both
both name the low rest on which someone seated sets the feetPsa 110:1
Only footstool
the plain English word sounds like ordinary household furniture, missing the throne-room setting and the note of worship or of conquest
How hadom differs from similar Hebrew words
כִּסֵּאthe throne, the seat of rule; the footstool is its lower companion, the rest for the feet where the king's presence reaches the ground and where beaten enemies are laid
Always a footstool, the low rest under the feet, and in the Old Testament it appears only in the phrase "footstool of his feet", a place of lowest honor before the one seated.Psa 110:1Psa 99:51Ch 28:2
Pictures subjection: enemies or the earth set under the feet, or in lament the holy place cast down and forgotten beneath God.Lam 2:1
Both
Both belong to the single picture of an enthroned king: God's throne is in heaven and the earth is the footstool beneath his feet, the seat above and the rest below forming one image of rule.Isa 66:1
The seat of the one who rules, an ordinary chair or, far more often, a royal throne, and so a standing symbol of the kingship and dynasty itself.1Ki 1:132Sa 7:13
Used of God's own throne in heaven, the place from which he reigns and judges, and of the thrones of foreign kings and officials.1Ki 22:19Gen 41:40
כֶּבֶשׁthe actual step or footstool of an earthly throne, such as Solomon's; this word by contrast is used only figuratively, for God's footstool
Reserved for the footstool of GOD, never of an ordinary person. It names the ark, Zion, the temple, and the whole earth as the place where the LORD sets his feet.1Ch 28:2Psa 99:5Isa 66:1
Carries the image of conquest: the LORD makes a king's enemies the footstool under his feet, a picture of total subjugation.Psa 110:1
A word of worship and lament, marking the spot before which people bow down and which God is said to spurn in his anger.Psa 132:7Lam 2:1
Both
Both name a footstool set before a royal throne, the low support for the feet of the one who reigns.Psa 110:12Ch 9:18
Names a literal piece of furniture: the golden footstool fastened to Solomon's throne, an object you could see and touch.2Ch 9:18
hadom in the other biblical languages
ὑποπόδιονGreek“footstool”the Greek word for footstool that the Greek Old Testament and the New Testament use to render and quote this one, above all in "make your enemies a footstool for your feet"
Never an everyday object: it always appears as the footstool of God's feet, pointing to the ark and the temple as the place his presence rests on earth, an object of worship1Ch 28:2Psa 99:5Psa 132:7
Can be turned into an image of judgment, when God is said to forget his own footstool as Zion fallsLam 2:1
Both
Both picture enemies made a footstool under the victor's feet, an image of total dominion; the New Testament word directly renders the Hebrew when it quotes this linePsa 110:1Act 2:35Heb 1:13
Both name the whole earth as God's footstool, a picture of how far above creation he sitsIsa 66:1Mat 5:35Act 7:49
Can name an ordinary piece of furniture, a real footstool a person sits beside in daily life, with no religious weight at allJas 2:3
What scholars say about hadom
הֲדֹם occurs six times, always in the bound phrase "footstool of the feet," and is solely metaphorical; the literal footstool of Solomon's throne (2 Chronicles 9:18) is called כֶּבֶשׁ. The older lexica (BDB, TWOT, older Gesenius) derived it from an unused Semitic root of trampling, but the continental tradition (Fabry in TDOT; Cornelius in NIDOTTE; Gesenius 18; HALOT) reads the root sense as "rest" and treats the word as shared Late Bronze Age vocabulary with Ugaritic hdm and Egyptian hdmw, direction of borrowing undetermined; Watson proposes a Hurrian source (admu). The image belongs to the wider royal ideology of a throne paired with a footstool ornamented with defeated foes, visible on Tutankhamun's inlaid footstool of nine bound captives and on Assyrian throne bases. On the Zion-theology reading (Haran, Mettinger, de Vaux, Seow) the ark is YHWH's footstool beneath the wings of the cherubim, which form an invisible throne; that reconstruction has been pressed by Weinfeld's demythologization thesis and challenged in turn by Wilson, by Japhet (who suspects the footstool language of 1 Chronicles 28:2 is a Chronistic innovation), and by Eichler (who grants the ark is a footstool but denies the wings form a seat). The Greek renders the word consistently as hypopodion; Psalm 110:1, on David Hay's count the most-cited Old Testament verse in the New Testament, supplies the christological image of enemies made a footstool (Luke 20:43;Acts 2:35;Hebrews 1:13; 10:13), with Mark 12:36 substituting "under your feet" by conflation with Psalm 8:6.
In-depth research
This is a research paper, so it may be hard to read without scholarly background. It is useful if you want to dig even deeper into this word.
Sources
L. Koehler and W. Baumgartner, HALOT, s.v. הֲדֹםlexicon
F. Brown, S. R. Driver, C. A. Briggs, BDB, 213, s.v. הֲדֹםlexicon