belonging to reason and to the word: engaging a person's thinking mind rather than mere outward ceremony or literal physical substance
This adjective is built straight on the Greek noun for "word" (λόγος), which in Greek also carries the sense of reason, argument, and account. So the adjective points two ways at once: toward what is done by reasoning thought, and toward what belongs to a word that has been spoken. Greek writers used it to mark human beings off from animals, calling a person a reasoning creature and the animals unreasoning (ἄλογος).
It appears only twice in the New Testament, and both times a translator has to choose which side of that double sense to put in front of the reader. In Romans 12:1 Paul asks Christians to offer their bodies as a living sacrifice and calls that their worship of this kind, which English Bibles have rendered "reasonable service", "rational worship", "spiritual worship", and "true and proper worship". In 1 Peter 2:2 newborn believers are told to crave pure milk of this kind, which comes out as either "spiritual milk" or "milk of the word".
The two uses lean in slightly different directions. In Paul the weight falls on the mind: the very next sentence speaks of being transformed by the renewing of the mind, so the worship he wants is offered knowingly and willingly, not by rote and not the way an animal is led to slaughter. In Peter the weight falls on the word: the letter has just said his readers were born again through God's living word, so the milk they crave belongs to that word and to the new life it started, and is plainly not the milk a baby drinks.
Greek philosophers and Greek-speaking Jewish writers had long used this word for worship offered by the mind rather than by killing animals, and the phrase Paul uses later became a standard name for the church's worship service in the East. That history is part of why no single English word works: the one Greek adjective holds reason, word, and "what befits a thinking creature" together.
Nuances
What λογικός denotes in Romans 12:1, and therefore how τὴν λογικὴν λατρείαν should be rendered.
- majorityIt denotes what is performed by reasoning thought, giving "rational", "reasoning", or "understanding" worship, in step with the renewal of the νοῦς in 12:2.; Douglas J. Moo, The Letter to the Romans, NICNT, 2nd ed. (Eerdmans, 2018); Thomas R. Schreiner, Romans, BECNT (Baker, 1998); James D. G. Dunn, Romans 9-16, WBC 38B (Word, 1988); Richard N. Longenecker, The Epistle to the Romans, NIGTC (Eerdmans, 2016); Ian W. Scott, "'Your Reasoning Worship': ΛΟΓΙΚΟΣ in Romans 12:1 and Paul's Ethics of Rational Deliberation," Journal of Theological Studies 69.2 (2018): 500-532; BDAG, s.v. λογικός ("thoughtful service" at Rom 12:1)
- minorityIt means "spiritual", in the sense of worship consistent with the truth revealed in Christ rather than mere outward ceremony.; C. E. B. Cranfield, The Epistle to the Romans, ICC (T&T Clark, 1975)
- minorityPaul alludes to the ancient philosophical discourse on the human vocation, best paralleled by Epictetus, Diss. 1.16.20-21, so the phrase is rendered "your genuinely human vocation".; Simon Dürr, Paul on the Human Vocation: Reason Language in Romans and Ancient Philosophical Tradition, BZNW 226 (De Gruyter, 2021); Melissa J. Barciela Mandala, review of Dürr, Bulletin for Biblical Research 33.3 (2023): 377-379
Whether τὸ λογικὸν ἄδολον γάλα in 1 Peter 2:2 is the milk that is the word of God (the λόγος of 1:23-25) or milk that is λογικός in the sense of "rational" or "spiritual", that is, not literal milk.
- majorityThe milk is the word of God: τὸ λογικόν looks back to the ζῶν λόγος of 1:23 and the ῥῆμα κυρίου of 1:25, so context fixes the referent even though the adjective does not by itself mean "of the word". This is the dominant reading in the commentary tradition and in the older English versions.; BDAG, s.v. λογικός ("pertaining to the message concerning Jesus Christ" at 1 Pet 2:2)
- minorityλογικός cannot substitute for the genitive τοῦ λόγου, so "milk of the word" is lexically impossible; the adjective means "rational", and the milk is the sustenance of the new life, with 2:3 pointing to craving the Lord himself rather than the written word alone.; Karen H. Jobes, 1 Peter, BECNT (Baker Academic, 2005); Karen H. Jobes, "Got Milk? Septuagint Psalm 33 and the Interpretation of 1 Peter 2:1-3," Westminster Theological Journal 64.1 (2002): 1-14; F. J. A. Hort, The First Epistle of St Peter I.1-II.17 (Macmillan, 1898); Francis W. Beare, The First Epistle of Peter (Blackwell, 1958)
- minorityλογικός here means "spiritual" in the sense of the human and divine plane of existence over against mere animal life, hence metaphorical rather than literal milk. BDAG notes this reading is frequent but judges it less likely.; J. Ramsey Michaels, 1 Peter, WBC 49 (Word, 1988)