Mystery
A "mystery", according to the Bible, is information that is not yet revealed or not fully disclosed by God.
Strong's Concordance
Hebrew
sathar : to hide, conceal
Original Word : סָתַר
Part of Speech : Verb
Transliteration : sathar
Phonetic Spelling : (saw-thar')
Definition : to hide, concealGreek
mustérion : a mystery or secret doctrine
Original Word : μυστήριον, ου, τό
Part of Speech : Noun, Neuter
Transliteration : mustérion
Phonetic Spelling : (moos-tay'-ree-on)
Definition : a mystery or secret doctrineMystery of God's essence
We must point out here the difference between mystery and contradiction; the former is something that cannot be fully explained to or comprehended by the human mind, whereas the latter is just nonsense — two concepts that cancel each other out and together make an absurdity. -- The book "Against Calvinism" written by Roger Olson
Often people will reason that you should not try to understand God or ask too many questions about God's essence. This is a very convenient counterargument to cancel any contradiction in scripture or logic. They will quote scriptures like:
1 Timothy 3:16
Great indeed, we confess, is the mystery of godliness. -- 1 Timothy 3:16 (ESV)
However, Paul was actually addressing a "church" who would have known Jesus. Jesus would have been no "mystery" to them. Instead, Paul was addressing a different issue, namely
They must hold the mystery of the faith with a clear conscience. -- 1 Timothy 3:9 (ESV)
which refers to
This charge I entrust to you, Timothy, my child, in accordance with the prophecies previously made about you, that by them you may wage the good warfare, holding faith and a good conscience. By rejecting this (gospel of the Christ), some have made shipwreck of their faith. -- 1 Timothy 1:18-19 (ESV)
In other words, to those who rejected the Christ, the gospel is a "mystery". This has nothing to do with understanding what God is.
1 Corinthians 13:12
For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall know fully, even as I have been fully known. -- 1 Corinthians 13:12 (ESV)
However, in this context Paul was referring to the gift of prophecy, tongues, and knowledge that only temporary nurture spiritual children who do not fully understand God's will.
- As for prophecies, they will pass away;
- as for tongues, they will cease;
- as for knowledge, it will pass away.
For we know in part and we prophesy in part, but when the perfect comes, the partial will pass away. When I was a child, I spoke like a child, I thought like a child, I reasoned like a child. When I became a man, I gave up childish ways. -- 1 Corinthians 13:8-11 (ESV)
Mystery of unfulfilled prophecies
Prophecies only indicates a partial or symbolic picture of what will happen in the future. The details become clear as the prophecy becomes fulfilled.
Making known to us the mystery of His will, according to his purpose, which he set forth in Christ as a plan for the fullness of time, to unite all things in him, things in heaven and things on earth. -- Ephesians 1:9-10 (ESV)
Lest you be wise in your own sight, I do not want you to be unaware of this mystery, brothers: a partial hardening has come upon Israel, until the fullness of the Gentiles has come in. -- Romans 11:25 (ESV)
For the mystery of lawlessness is already at work. Only he who now restrains it will do so until he is out of the way. -- 2 Thessalonians 2:7 (ESV)
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. -- Revelation 10:7 (ESV)
They must hold the mystery of the faith with a clear conscience. -- 1 Timothy 3:9 (ESV)
which refers to
This charge I entrust to you, Timothy, my child, in accordance with the prophecies previously made about you, that by them you may wage the good warfare, holding faith and a good conscience. By rejecting this, some have made shipwreck of their faith. -- 1 Timothy 1:18-19 (ESV)
Mystery of the lack of revelation from God
A "mystery" could also be information that is concealed or was temporary unavailable or not well understood when had been revealed by God.
“The secret things belong to the LORD our God, but the things that are revealed belong to us and to our children forever, that we may do all the words of this law. -- Deuteronomy 29:29 (ESV)
Call to Me and I will answer you, and will tell you great and hidden things that you have not known. -- Jeremiah 33:3 (ESV)
“For the LORD God does nothing without revealing His secret to his servants the prophets. -- Amos 3:7 (ESV)
Some examples from Daniel:
Daniel answered the king and said, “No wise men, enchanters, magicians, or astrologers can show to the king the mystery that the king has asked, -- Daniel 2:27 (ESV)
But as for me, this mystery has been revealed to me, not because of any wisdom that I have more than all the living, but in order that the interpretation may be made known to the king, and that you may know the thoughts of your mind. -- Daniel 2:30 (ESV)
Some examples from the Gospels:
At that time Jesus declared, “I thank you, Father, Lord of heaven and earth, that you have hidden these things from the wise and understanding and revealed them to little children; -- Matthew 11:25 (ESV)
And he answered them, “To you it has been given to know the secrets of the kingdom of heaven, but to them it has not been given. For to the one who has, more will be given, and he will have an abundance, but from the one who has not, even what he has will be taken away. This is why I speak to them in parables, because seeing they do not see, and hearing they do not hear, nor do they understand. -- Matthew 13:11-13 (ESV)
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.’ -- Luke 8:10 (ESV)
And he said to them, “To you has been given the secret of the kingdom of God, but for those outside everything is in parables, -- Mark 4:11 (ESV)
Examples from Ephesians:
Assuming that you have heard of the stewardship of God's grace that was given to me for you, how the mystery was made known to me by revelation, as I have written briefly. When you read this, you can perceive my insight into the mystery of Christ, which was not made known to the sons of men in other generations as it has now been revealed to his holy apostles and prophets by the Spirit. This mystery is that the Gentiles are fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel. -- Ephesians 3:2-6 (ESV)
And to bring to light for everyone what is the plan of the mystery hidden for ages in God, who created all things, -- Ephesians 3:9 (ESV)
In the same way husbands should love their wives as their own bodies. He who loves his wife loves himself. For no one ever hated his own flesh, but nourishes and cherishes it, just as Christ does the church, because we are members of his body. “Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh.” This mystery is profound, and I am saying that it refers to Christ and the church. -- Ephesians 5:28-32 (ESV)
And also for me, that words may be given to me in opening my mouth boldly to proclaim the mystery of the gospel, -- Ephesians 6:19 (ESV)
Examples from Corinthians:
But we speak the wisdom of God in a mystery, the hidden wisdom which God ordained before the ages for our glory, -- 1 Corinthians 2:7 (NKJV)
This is how one should regard us, as servants of Christ and stewards of the mysteries of God. -- 1 Corinthians 4:1 (ESV)
I tell you this, brothers: flesh and blood cannot inherit the kingdom of God, nor does the perishable inherit the imperishable. Behold! I tell you a mystery. We shall not all sleep, but we shall all be changed, in a moment, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, and the dead will be raised imperishable, and we shall be changed. For this perishable body must put on the imperishable, and this mortal body must put on immortality. -- 1 Corinthians 15:50-53 (ESV)
Examples from Colossians:
Of which I became a minister according to the stewardship from God that was given to me for you, to make the word of God fully known, the mystery hidden for ages and generations but now revealed to his saints. To them God chose to make known how great among the Gentiles are the riches of the glory of this mystery, which is Christ in you, the hope of glory. -- Colossians 1:25-27 (ESV)
For I want you to know how great a struggle I have for you and for those at Laodicea and for all who have not seen me face to face, that their hearts may be encouraged, being knit together in love, to reach all the riches of full assurance of understanding and the knowledge of God's mystery, which is Christ, in whom are hidden all the treasures of wisdom and knowledge. -- Colossians 2:1-3 (ESV)
Examples from Revelations:
As for the mystery of the seven stars that you saw in my right hand, and the seven golden lampstands, the seven stars are the angels of the seven churches, and the seven lampstands are the seven churches. -- Revelation 1:20 (ESV)
And on her forehead was written a name of mystery: “Babylon the great, mother of prostitutes and of earth's abominations.” -- Revelation 17:5 (ESV)
But the angel said to me, “Why do you marvel? I will tell you the mystery of the woman and of the beast with seven heads and ten horns that carries her. -- Revelation 17:7 (ESV)
Other examples:
Now to him who is able to strengthen you according to my gospel and the preaching of Jesus Christ, according to the revelation of the mystery that was kept secret for long ages but has now been disclosed and through the prophetic writings has been made known to all nations, according to the command of the eternal God, to bring about the obedience of faith— -- Romans 16:25-26 (ESV)
Great indeed, we confess, is the mystery of godliness: He was manifested in the flesh, vindicated by the Spirit, seen by angels, proclaimed among the nations, believed on in the world, taken up in glory. -- 1 Timothy 3:16 (ESV)