Strong’s G4603: An adjective meaning “made of iron,” derived from σίδηρος (iron). In biblical usage, it appears in contexts emphasizing strength, authority, or oppression. The word carries connotations of both power and inflexibility, often used metaphorically in prophetic and apocalyptic literature.

U- Unveiling the Word

σιδηροῦς represents both literal iron construction and metaphorical strength or inflexibility. First appearing in Acts 12:10 describing the prison gate that miraculously opened for Peter, it symbolizes seemingly insurmountable barriers that God can overcome. Early church writers saw in this word both the reality of persecution (iron chains) and the power of God to deliver. Today, it reminds us that no barrier, however strong, can withstand God’s purpose.

N – Necessary Information

• Greek Word: σιδηροῦς, sidērous, see-day-ROOS
• Detailed pronunciation: stress on last syllable: ‘see’ as in see, ‘day’ as in day, ‘ROOS’ as in roost
• Part of Speech: Adjective

Etymology:

• From σίδηρος (sidēros) – iron
• -οῦς (-ous): Adjectival ending indicating material composition

D – Defining Meanings

• Made of iron
• Iron-like
• Strong as iron

For compound words:
Not applicable as σιδηροῦς is derived with an adjectival suffix

Translation Options:

• “Iron” – When used attributively
• “Made of iron” – More explicit
• “Iron-like” – When used metaphorically

E – Exploring Similar Words

• χαλκοῦς (chalkous, khal-KOOS) – made of brass See G5470
• χρυσοῦς (chrusous, khroo-SOOS) – made of gold See G5552
• ἀργυροῦς (argurous, ar-goo-ROOS) – made of silver See G693

R – Reviewing the Word’s Morphology

Adjective Features:

• Case: Nominative, Genitive, Dative, Accusative
• Number: Singular, Plural
• Gender: Masculine, Feminine, Neuter
• Declension: Contract adjective (2nd/1st)

Examples:
Masculine: σιδηροῦς (nom), σιδηροῦ (gen)
Feminine: σιδηρᾶ (nom), σιδηρᾶς (gen)
Neuter: σιδηροῦν (nom/acc), σιδηροῦ (gen)

S – Studying Lexicon Insights

BDAG emphasizes both literal and metaphorical uses. Thayer’s notes its connection to strength and authority. LSJ documents its use in technical contexts. Vine’s highlights its symbolic significance. Strong’s connects it to unbending strength. Moulton-Milligan provides evidence from commercial documents.

T – Tracing the Scriptures

First appearance:
“When they were past the first and the second ward, they came unto the iron gate that leadeth unto the city; which opened to them of his own accord:” Acts 12:10

Additional References:
Revelation 2:27, Revelation 9:9, Revelation 12:5, Revelation 19:15

A – Analyzing Classical Usage

N – Noteworthy Summary

σιδηροῦς reminds us that even the strongest earthly barriers cannot resist God’s will. Whether literal iron gates or metaphorical obstacles, all yield to divine power. The word points to Christ’s ultimate authority, who rules with an iron scepter yet uses His power for redemption.

D – Did You Know?

1. Iron was the strongest metal known in biblical times.
2. The term often symbolized Roman power in early Christian literature.
3. The “iron scepter” imagery in Revelation draws from Psalm 2.

Strong’s G4603: An adjective meaning “made of iron,” derived from σίδηρος (iron). In biblical usage, it appears in contexts emphasizing strength, authority, or oppression. The word carries connotations of both power and inflexibility, often used metaphorically in prophetic and apocalyptic literature.

Part of speech: Adjective

Tags: iron, strength, power, divine authority, barriers, persecution, deliverance, Revelation, apocalyptic imagery, Roman power, divine sovereignty, material qualities​​​​​​​​​​​​​​​​