στερεός

solid, firm, steadfast

Definition

The adjective στερεός primarily means 'solid, firm, or steadfast,' describing something with physical or moral substance that does not easily give way. In a physical sense, it refers to solid food in contrast to milk (Hebrews 5:12, 14), indicating advanced, substantial teaching. In a metaphorical sense, it describes the unshakeable, reliable foundation of God in 2 Timothy 2:19 ('the firm foundation of God stands'). It also characterizes the steadfastness of faith required to resist the devil in 1 Peter 5:9.

Biblical Usage

Used four times in the New Testament, στερεός appears in didactic (teaching) and exhortatory contexts. In Hebrews, it contrasts elementary spiritual instruction ('milk') with mature doctrine ('solid food'). In the pastoral epistles and general epistles, it describes the unwavering nature of God's truth and the resolute faith of believers. Key verses are 2 Timothy 2:19, Hebrews 5:12, Hebrews 5:14, and 1 Peter 5:9.

Etymology

Derived from the Proto-Indo-European root *ster-, meaning 'stiff, rigid, firm.' The Greek στερεός is related to words like στερεόω (stereoō, G4732) meaning 'to make firm or solid' and the English 'stereo-' (as in three-dimensional solidity). Its core meaning of physical solidity extended metaphorically to moral and spiritual firmness.

Semantic Range

This word is theologically significant as it connects spiritual maturity with doctrinal stability. The 'solid food' in Hebrews represents the deeper truths of righteousness, requiring developed discernment. It underscores that God's foundation and truth are unchangeable (2 Timothy 2:19), and the Christian's faith must be equally firm to withstand spiritual opposition (1 Peter 5:9). Understanding this Greek term enriches reading by highlighting the call from spiritual infancy to a robust, resilient faith.

In the ancient Greco-Roman world, 'solid food' was a common metaphor for advanced philosophical or complex teaching, contrasting with the 'milk' given to infants or beginners. This cultural understanding directly informs the author of Hebrews' analogy for spiritual growth. The idea of a 'firm foundation' would resonate in a context familiar with architectural stability and reliable civic institutions.

βεβαίος (bebaios, G949) — emphasizes reliability and confirmation, often of a promise or covenant. ἑδραῖος (hedraios, G1476) — stresses being settled, immovable, like a building's foundation. πιστός (pistos, G4103) — focuses on faithfulness and trustworthiness, more relational.

Word Details

Scripture References