Except they're not vague, you're just not aware of them. They're quite specific. Look at Isaiah 53 for example.
Who has believed our message?
And to whom has the arm of the Lord been revealed?
For He grew up before Him like a tender shoot,
And like a root out of parched ground;
He has no stately form or majesty
That we should look upon Him,
Nor appearance that we should be attracted to Him.
He was despised and forsaken of men,
A man of sorrows and acquainted with grief;
And like one from whom men hide their face
He was despised, and we did not esteem Him.
Surely our griefs He Himself bore,
And our sorrows He carried;
Yet we ourselves esteemed Him stricken,
Smitten of God, and afflicted.
But He was pierced through for our transgressions,
He was crushed for our iniquities;
The chastening for our well-being fell upon Him,
And by His scourging we are healed.
All of us like sheep have gone astray,
Each of us has turned to his own way;
But the Lord has caused the iniquity of us all
To fall on Him.
He was oppressed and He was afflicted,
Yet He did not open His mouth;
Like a lamb that is led to slaughter,
And like a sheep that is silent before its shearers,
So He did not open His mouth.
By oppression and judgment He was taken away;
And as for His generation, who considered
That He was cut off out of the land of the living
For the transgression of my people, to whom the stroke was due?
His grave was assigned with wicked men,
Yet He was with a rich man in His death,
Because He had done no violence,
Nor was there any deceit in His mouth.
But the Lord was pleased
To crush Him, putting Him to grief;
If He would render Himself as a guilt offering,
He will see His offspring,
He will prolong His days,
And the good pleasure of the Lord will prosper in His hand.
As a result of the anguish of His soul,
He will see it and be satisfied;
By His knowledge the Righteous One,
My Servant, will justify the many,
As He will bear their iniquities.
Therefore, I will allot Him a portion with the great,
And He will divide the booty with the strong;
Because He poured out Himself to death,
And was numbered with the transgressors;
Yet He Himself bore the sin of many,
And interceded for the transgressors.
— Isaiah 53:1-12
“If a prophet or a dreamer of dreams arises among you and gives you a sign or a wonder, and the sign or the wonder comes true, concerning which he spoke to you, saying, ‘Let us go after other gods (whom you have not known) and let us serve them,’ you shall not listen to the words of that prophet or that dreamer of dreams; for the Lord your God is testing you to find out if you love the Lord your God with all your heart and with all your soul. You shall follow the Lord your God and fear Him; and you shall keep His commandments, listen to His voice, serve Him, and cling to Him. But that prophet or that dreamer of dreams shall be put to death, because he has counseled rebellion against the Lord your God who brought you from the land of Egypt and redeemed you from the house of slavery, to seduce you from the way in which the Lord your God commanded you to walk. So you shall purge the evil from among you.
— Deuteronomy 13:1-5
For false Christs and false prophets will arise and will show great signs and wonders, so as to mislead, if possible, even the elect. Behold, I have told you in advance.
— Matthew 24:24-25
Then that lawless one will be revealed whom the Lord will slay with the breath of His mouth and bring to an end by the appearance of His coming; that is, the one whose coming is in accord with the activity of Satan, with all power and signs and false wonders, and with all the deception of wickedness for those who perish, because they did not receive the love of the truth so as to be saved. For this reason God will send upon them a deluding influence so that they will believe what is false, in order that they all may be judged who did not believe the truth, but took pleasure in wickedness.
— 2 Thessalonians 2:8-12
Except they're not vague, you're just not aware of them. They're quite specific. Look at Isaiah 53 for example.
Who has believed our message? And to whom has the arm of the Lord been revealed? For He grew up before Him like a tender shoot, And like a root out of parched ground; He has no stately form or majesty That we should look upon Him, Nor appearance that we should be attracted to Him. He was despised and forsaken of men, A man of sorrows and acquainted with grief; And like one from whom men hide their face He was despised, and we did not esteem Him. Surely our griefs He Himself bore, And our sorrows He carried; Yet we ourselves esteemed Him stricken, Smitten of God, and afflicted. But He was pierced through for our transgressions, He was crushed for our iniquities; The chastening for our well-being fell upon Him, And by His scourging we are healed. All of us like sheep have gone astray, Each of us has turned to his own way; But the Lord has caused the iniquity of us all To fall on Him. He was oppressed and He was afflicted, Yet He did not open His mouth; Like a lamb that is led to slaughter, And like a sheep that is silent before its shearers, So He did not open His mouth. By oppression and judgment He was taken away; And as for His generation, who considered That He was cut off out of the land of the living For the transgression of my people, to whom the stroke was due? His grave was assigned with wicked men, Yet He was with a rich man in His death, Because He had done no violence, Nor was there any deceit in His mouth. But the Lord was pleased To crush Him, putting Him to grief; If He would render Himself as a guilt offering, He will see His offspring, He will prolong His days, And the good pleasure of the Lord will prosper in His hand. As a result of the anguish of His soul, He will see it and be satisfied; By His knowledge the Righteous One, My Servant, will justify the many, As He will bear their iniquities. Therefore, I will allot Him a portion with the great, And He will divide the booty with the strong; Because He poured out Himself to death, And was numbered with the transgressors; Yet He Himself bore the sin of many, And interceded for the transgressors. — Isaiah 53:1-12
“If a prophet or a dreamer of dreams arises among you and gives you a sign or a wonder, and the sign or the wonder comes true, concerning which he spoke to you, saying, ‘Let us go after other gods (whom you have not known) and let us serve them,’ you shall not listen to the words of that prophet or that dreamer of dreams; for the Lord your God is testing you to find out if you love the Lord your God with all your heart and with all your soul. You shall follow the Lord your God and fear Him; and you shall keep His commandments, listen to His voice, serve Him, and cling to Him. But that prophet or that dreamer of dreams shall be put to death, because he has counseled rebellion against the Lord your God who brought you from the land of Egypt and redeemed you from the house of slavery, to seduce you from the way in which the Lord your God commanded you to walk. So you shall purge the evil from among you. — Deuteronomy 13:1-5
For false Christs and false prophets will arise and will show great signs and wonders, so as to mislead, if possible, even the elect. Behold, I have told you in advance. — Matthew 24:24-25
Then that lawless one will be revealed whom the Lord will slay with the breath of His mouth and bring to an end by the appearance of His coming; that is, the one whose coming is in accord with the activity of Satan, with all power and signs and false wonders, and with all the deception of wickedness for those who perish, because they did not receive the love of the truth so as to be saved. For this reason God will send upon them a deluding influence so that they will believe what is false, in order that they all may be judged who did not believe the truth, but took pleasure in wickedness. — 2 Thessalonians 2:8-12