Romans 1:21

For even though they knew God [as the Creator], they did not honor Him as God or give thanks [for His wondrous creation]. On the contrary, they became worthless in their thinking [godless, with pointless reasonings, and silly speculations], and their foolish heart was darkened.

Jeremiah 2:5

Thus says the Lord,

“What injustice or unrighteousness did your fathers find in Me,
That they have wandered far from Me
And [habitually] walked after emptiness and futility and became empty?

Ephesians 4:17-18

So this I say, and solemnly affirm together with the Lord [as in His presence], that you must no longer live as the [unbelieving] Gentiles live, in the futility of their minds [and in the foolishness and emptiness of their souls],

2 Kings 17:15

They rejected His statutes and His covenant which He made with their fathers, as well as His warnings that he gave them. And they followed vanity [that is, false gods, idols] and became vain (empty-headed). They followed the [pagan practices of the] nations which surrounded them, although the Lord had commanded that they were not to do as they did.

Romans 1:19

because that which is known about God is evident within them [in their inner consciousness], for God made it evident to them.

Revelation 14:7

and he said with a loud voice, “Fear God [with awe and reverence], and give Him glory [and honor and praise in worship], because the hour of His judgment has come; [with all your heart] worship Him who created the heaven and the earth, the sea and the springs of water.”

Genesis 6:5

The Lord saw that the wickedness (depravity) of man was great on the earth, and that every imagination or intent of the thoughts of his heart were only evil continually.

Genesis 8:21

The Lord smelled the pleasing aroma [a soothing, satisfying scent] and the Lord said to Himself, “I will never again curse the ground because of man, for the intent (strong inclination, desire) of man’s heart is wicked from his youth; and I will never again destroy every living thing, as I have done.

Deuteronomy 28:29

and you will be groping at noon [in broad daylight], just as the blind grope in the darkness, and nothing you do will prosper; but you will only be oppressed and exploited and robbed continually, with no one to save you.

Psalm 50:23


“He who offers a sacrifice of praise and thanksgiving honors Me;
And to him who orders his way rightly [who follows the way that I show him],
I shall show the salvation of God.”

Psalm 81:12


“So I gave them up to the stubbornness of their heart,
To walk in [the path of] their own counsel.

Psalm 86:9


All nations whom You have made shall come and kneel down in worship before You, O Lord,
And they shall glorify Your name.

Ecclesiastes 7:29

Behold, I have found only this [as a reason]: God made man upright and uncorrupted, but they [both men and women] have sought out many devices [for evil].”

Isaiah 44:9-20

All who make carved idols are nothing. Their precious objects are worthless [to them], and their own witnesses (worshipers) fail to see or know, so that they will be put to shame.

Isaiah 60:2


“For in fact, darkness will cover the earth
And deep darkness will cover the peoples;
But the Lord will rise upon you [Jerusalem]
And His glory and brilliance will be seen on you.

Jeremiah 10:3-8


For the customs and decrees of the peoples are [mere] delusion [exercises in futility];
It is only wood which one cuts from the forest [to make a god],
The work of the hands of the craftsman with the axe or cutting tool.

Jeremiah 10:14-15


Every man has become [like a brute] irrational and stupid, without knowledge [of God];
Every goldsmith is shamed by his carved idols;
For his molten images are frauds and lies,
And there is no breath in them.

Jeremiah 16:19


[Then said Jeremiah] “O Lord, my Strength and my Stronghold,
And my Refuge in the day of distress and need,
The nations will come to You
From the ends of the earth and say,
‘Our fathers have inherited nothing but lies and illusion,
[Worthless] things in which there is no benefit!’

Hosea 2:8


“For she (Israel) has not noticed nor understood nor realized that it was I [the Lord God] who gave her the grain and the new wine and the oil,
And lavished on her silver and gold,
Which they used for Baal and made into his image.

Habakkuk 1:15-16


The Chaldeans bring all of them up with a hook,
And drag them away with a net,
And gather them together in their fishing net;
So they rejoice and are glad.

Luke 17:15-18

One of them, when he saw that he was healed, turned back, glorifying and praising and honoring God with a loud voice;

John 3:19

This is the judgment [that is, the cause for indictment, the test by which people are judged, the basis for the sentence]: the Light has come into the world, and people loved the darkness rather than the Light, for their deeds were evil.

Romans 1:28

And since they did not see fit to acknowledge God or consider Him worth knowing [as their Creator], God gave them over to a depraved mind, to do things which are improper and repulsive,

Romans 11:10


Let their eyes be darkened so that they do not see,
And make their backs bend [under their burden] forever.”

Romans 15:9

and for the Gentiles to glorify God for His mercy [to them, since God had no covenant with them]. As it is written and forever remains written,

Therefore I praise You among the Gentiles,
And sing praises to Your name.”

2 Timothy 3:2

For people will be lovers of self [narcissistic, self-focused], lovers of money [impelled by greed], boastful, arrogant, revilers, disobedient to parents, ungrateful, unholy and profane,

1 Peter 1:18

For you know that you were not redeemed from your useless [spiritually unproductive] way of life inherited [by tradition] from your forefathers with perishable things like silver and gold,

1 Peter 2:9

But you are a chosen race, a royal priesthood, a consecrated nation, a [special] people for God’s own possession, so that you may proclaim the excellencies [the wonderful deeds and virtues and perfections] of Him who called you out of darkness into His marvelous light.

Revelation 15:4


“Who will not fear [reverently] and glorify Your name, O Lord [giving You honor and praise in worship]?
For You alone are holy;
For all the nations shall come and worship before You,
For Your righteous acts [Your just decrees and judgments] have been revealed and displayed.”

Acts 26:18

to open their [spiritual] eyes so that they may turn from darkness to light and from the power of Satan to God, that they may receive forgiveness and release from their sins and an inheritance among those who have been sanctified (set apart, made holy) by faith in Me.’

Treasury of Scripture Knowledge

Summary

Because that, when they knew God, they glorified him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.

Bible References

When

Romans 1:19
because that which is known about God is evident within them [in their inner consciousness], for God made it evident to them.
John 3:19
This is the judgment [that is, the cause for indictment, the test by which people are judged, the basis for the sentence]: the Light has come into the world, and people loved the darkness rather than the Light, for their deeds were evil.

They glorified

Romans 15:9
and for the Gentiles to glorify God for His mercy [to them, since God had no covenant with them]. As it is written and forever remains written,

Therefore I praise You among the Gentiles,
And sing praises to Your name.”
Psalm 50:23

“He who offers a sacrifice of praise and thanksgiving honors Me;
And to him who orders his way rightly [who follows the way that I show him],
I shall show the salvation of God.”
Psalm 86:9

All nations whom You have made shall come and kneel down in worship before You, O Lord,
And they shall glorify Your name.
Hosea 2:8

“For she (Israel) has not noticed nor understood nor realized that it was I [the Lord God] who gave her the grain and the new wine and the oil,
And lavished on her silver and gold,
Which they used for Baal and made into his image.
Habakkuk 1:15

The Chaldeans bring all of them up with a hook,
And drag them away with a net,
And gather them together in their fishing net;
So they rejoice and are glad.
Luke 17:15
One of them, when he saw that he was healed, turned back, glorifying and praising and honoring God with a loud voice;
2 Timothy 3:2
For people will be lovers of self [narcissistic, self-focused], lovers of money [impelled by greed], boastful, arrogant, revilers, disobedient to parents, ungrateful, unholy and profane,
Revelation 14:7
and he said with a loud voice, “Fear God [with awe and reverence], and give Him glory [and honor and praise in worship], because the hour of His judgment has come; [with all your heart] worship Him who created the heaven and the earth, the sea and the springs of water.”
Revelation 15:4

“Who will not fear [reverently] and glorify Your name, O Lord [giving You honor and praise in worship]?
For You alone are holy;
For all the nations shall come and worship before You,
For Your righteous acts [Your just decrees and judgments] have been revealed and displayed.”

But became

Genesis 6:5
The Lord saw that the wickedness (depravity) of man was great on the earth, and that every imagination or intent of the thoughts of his heart were only evil continually.
Genesis 8:21
The Lord smelled the pleasing aroma [a soothing, satisfying scent] and the Lord said to Himself, “I will never again curse the ground because of man, for the intent (strong inclination, desire) of man’s heart is wicked from his youth; and I will never again destroy every living thing, as I have done.
2 Kings 17:15
They rejected His statutes and His covenant which He made with their fathers, as well as His warnings that he gave them. And they followed vanity [that is, false gods, idols] and became vain (empty-headed). They followed the [pagan practices of the] nations which surrounded them, although the Lord had commanded that they were not to do as they did.
Psalm 81:12

“So I gave them up to the stubbornness of their heart,
To walk in [the path of] their own counsel.
Ecclesiastes 7:29
Behold, I have found only this [as a reason]: God made man upright and uncorrupted, but they [both men and women] have sought out many devices [for evil].”
Isaiah 44:9
All who make carved idols are nothing. Their precious objects are worthless [to them], and their own witnesses (worshipers) fail to see or know, so that they will be put to shame.
Jeremiah 2:5
Thus says the Lord,

“What injustice or unrighteousness did your fathers find in Me,
That they have wandered far from Me
And [habitually] walked after emptiness and futility and became empty?
Jeremiah 10:3

For the customs and decrees of the peoples are [mere] delusion [exercises in futility];
It is only wood which one cuts from the forest [to make a god],
The work of the hands of the craftsman with the axe or cutting tool.
Jeremiah 16:19

[Then said Jeremiah] “O Lord, my Strength and my Stronghold,
And my Refuge in the day of distress and need,
The nations will come to You
From the ends of the earth and say,
‘Our fathers have inherited nothing but lies and illusion,
[Worthless] things in which there is no benefit!’
Ephesians 4:17
So this I say, and solemnly affirm together with the Lord [as in His presence], that you must no longer live as the [unbelieving] Gentiles live, in the futility of their minds [and in the foolishness and emptiness of their souls],
1 Peter 1:18
For you know that you were not redeemed from your useless [spiritually unproductive] way of life inherited [by tradition] from your forefathers with perishable things like silver and gold,

Their foolish

Romans 11:10

Let their eyes be darkened so that they do not see,
And make their backs bend [under their burden] forever.”
Deuteronomy 28:29
and you will be groping at noon [in broad daylight], just as the blind grope in the darkness, and nothing you do will prosper; but you will only be oppressed and exploited and robbed continually, with no one to save you.
Isaiah 60:2

“For in fact, darkness will cover the earth
And deep darkness will cover the peoples;
But the Lord will rise upon you [Jerusalem]
And His glory and brilliance will be seen on you.
Acts 26:18
to open their [spiritual] eyes so that they may turn from darkness to light and from the power of Satan to God, that they may receive forgiveness and release from their sins and an inheritance among those who have been sanctified (set apart, made holy) by faith in Me.’
1 Peter 2:9
But you are a chosen race, a royal priesthood, a consecrated nation, a [special] people for God’s own possession, so that you may proclaim the excellencies [the wonderful deeds and virtues and perfections] of Him who called you out of darkness into His marvelous light.

General references

Psalm 94:11

The Lord knows the thoughts of man,
That they are a mere breath (vain, empty, futile).
Isaiah 40:21

Do you [who worship idols] not know? Have you not heard?
Has it not been told to you from the beginning?
Have you not understood from the foundations of the earth [the omnipotence of God and the stupidity of bowing to idols]?
Jeremiah 33:18
and the Levitical priests shall never lack a man (descendant) to offer burnt offerings before Me and to burn grain offerings and to prepare sacrifices all day long.’”
James 4:17
So any person who knows what is right to do but does not do it, to him it is sin.