Three usages of G3466-mystērion

Strong's Greek: 3466. μυστήριον (mustérion) — 28 Occurrences

BDAG:

‘secret, secret rite, secret teaching, mystery’ a relig. t.t. (predom. pl.) applied in the Gr-Rom. world mostly to the mysteries w. their secret teachings, relig. and political in nature, concealed within many strange customs and ceremonies. The principal rites remain unknown because of a reluctance in antiquity to divulge them

① the unmanifested or private counsel of God, (God’s) secret, the secret thoughts, plans, and dispensations of God … which are hidden fr. human reason, as well as fr. all other comprehension below the divine level, and await either fulfillment or revelation to those for whom they are intended

There were three nuances:

1. Jesus revealed the mysteries of the parables to his disciples. Many outsiders could not understand.

ⓐ In the gospels μ. is found only in one context, where Jesus says to the disciples who have asked for an explanation of the parable(s)

Lk 8:

8b As [Jesus] said these things, he called out, “He who has ears to hear, let him hear.” 9 And when his disciples asked him what this parable meant, 10 he said, “To you it has been given to know the secrets of the kingdom of God, but for others they are in parables, so that ‘seeing they may not see, and hearing they may not understand.’

This reflects a fulfillment of Isaiah 6:9. The parables both reveal and conceal, depending on the listener's heart condition.

2. Paul spoke on doctrinal mysteries: Gentile salvation (Ep 3:6), the resurrection transformation at Christ’s return (1C 15:51), the mystery of godliness (1Tm 3:16), the mystery of lawlessness (2Th 2:7), the mystery of Christ indwelling believers (Col 1:27). Some believers knew and some didn't.

ⓑ The Pauline lit. has μ. in 21 places. A secret or mystery, too profound for human ingenuity … is God’s reason for the partial hardening of Israel’s heart Ro 11:25 or the transformation of the surviving Christians at the Parousia 1 Cor 15:51. Even Christ, who was understood by so few, is God’s secret or mystery Col 2:2, hidden ages ago 1:26 … but now gloriously revealed among the gentiles vs. 27, to whom the secret of Christ, i.e. his relevance for them, is proclaimed, 4:3. Not all Christians are capable of understanding all the mysteries.

1C 14:

2 For the one who speaks in a tongue does not speak to people but to God, because no one understands, but by the Spirit he speaks mysteries.

Not all believers grasp every mystery. Some require spiritual maturity (1C 2:6–10). Yet, these mysteries form the core of Christian theology.

3. John wrote about eschatological mysteries. These were difficult to understand for believers and non-believers.

ⓒ In Rv μ. is used in ref. to the mysterious things portrayed there. The whole content of the book appears as τὸ μ. τοῦ θεοῦ 10:7.

Re 10:

7 In the days of the trumpet call to be sounded by the seventh angel, the mystery of God would be fulfilled, just as he announced to his servants the prophets.

Re 17:

7 And the angel said to me, “Why are you astonished? I will tell you the mystery of the woman and of the beast that has the seven heads and the ten horns that carries her.

Here, "mystery" refers to prophetic truths veiled in symbolic language, often involving end-times events and divine judgments.

In all three nuances, a mystery is not unknowable — it is knowable only through divine revelation. Whether in Jesus’ parables, Paul’s doctrines, or John’s prophecies, the unveiling of these mysteries depends on God’s initiative and the believer’s openness to receive spiritual insight.