New Revised Standard Version
for though they knew God, they did not honor him as God or give thanks to him, but they became futile in their thinking, and their senseless minds were darkened.

Contemporary English Version
They know about God, but they don't honor him or even thank him. Their thoughts are useless, and their stupid minds are in the dark.

New American Bible
for although they knew God they did not accord him glory as God or give him thanks. Instead, they became vain in their reasoning, and their senseless minds were darkened.

Douay-Rheims Bible
Because that, when they knew God, they have not glorified him as God or given thanks: but became vain in their thoughts. And their foolish heart was darkened.

Because that, when they knew God, they have not glorified him as God or given thanks: but became vain in their thoughts. And their foolish heart was darkened.

when.

Romans 1:19,28 Because that which is known of God is manifest in them. For God hath manifested it unto them. . . .

John 3:19 And this is the judgment: Because the light is come into the world and men loved darkness rather than the light: for their works were evil.

they glorified.

Romans 15:9 But that the Gentiles are to glorify God for his mercy, as it is written: Therefore will I confess to thee, O Lord, among the Gentiles and will sing to thy name.

Psalm 50:23 The sacrifice of praise shall glorify me: and there is the way by which I will shew him the salvation of God.

Psalm 86:9 All the nations thou hast made shall come and adore before thee, O Lord: and they shall glorify thy name.

Hosea 2:8 And she did not know that I gave her corn, and wine, and oil, and multiplied her silver, and gold, which they have used in the service of Baal.

Habakkuk 1:15,16 He lifted up all them with his hook, he drew them in his drag, and gathered them into his net: for this he will be glad and rejoice. . . .

Luke 17:15-18 And one of them, when he saw that he was made clean, went back, with a loud voice glorifying God. . . .

2 Timothy 3:2 Men shall be lovers of themselves, covetous, haughty, proud, blasphemers, disobedient to parents, ungrateful, wicked,

Revelation 14:7 Saying with a loud voice: Fear the Lord and give him honour, because the hour of his judgment is come. And adore ye him that made heaven and earth, the sea and the fountains of waters.

Revelation 15:4 Who shall not fear thee, O Lord, and magnify thy name? For thou only art holy. For all nations shall come and shall adore in thy sight, because thy judgments are manifest.

but became.

Genesis 6:5 And God seeing that the wickedness of men was great on the earth, and that all the thought of their heart was bent upon evil at all times,

Genesis 8:21 And the Lord smelled a sweet savour, and said: I will no more curse the earth for the sake of man: for the imagination and thought of man's heart are prone to evil from his youth: therefore I will no more destroy every living soul as I have done.

2 Kings 17:15 And they rejected his ordinances, and the covenant that he made with their fathers, and the testimonies which he testified against them: and they followed vanities, and acted vainly: and they followed the nations that were round about them, concerning which the Lord had commanded them that they should not do as they did.

Psalm 81:12 So I let them go according to the desires of their heart: they shall walk in their own inventions.

Ecclesiastes 7:29 Only this I have found, that God made man right, and he hath entangled himself with an infinity of questions. Who is as the wise man? and who hath known the resolution of the word?

Isaiah 44:9-20 The makers of idols are all of them nothing, and their best beloved things shall not profit them. They are their witnesses, that they do not see, nor understand, that they may be ashamed. . . .

Jeremiah 2:5 Thus saith the Lord: What iniquity have your fathers found in me, that they are gone far from me, and have walked after vanity, and are become vain?

Jeremiah 10:3-8,14,15 For the laws of the people are vain: for the works of the hand of the workman hath cut a tree out of the forest with an axe. . . .

Jeremiah 16:19 O Lord, my might, and my strength, and my refuge in the day of tribulation: to thee the Gentiles shall come from the ends of the earth, and shall say: Surely our fathers have possessed lies, a vanity which hath not profited them.

Ephesians 4:17,18 This then I say and testify in the Lord: That henceforward you walk not as also the Gentiles walk in the vanity of their mind: . . .

1 Peter 1:18 Knowing that you were not redeemed with corruptible things, as gold or silver, from your vain conversation of the tradition of your fathers:

their foolish.

Romans 11:10 Let their eyes be darkened, that they may not see: and bow down their back always.

Deuteronomy 28:29 And mayst thou grope at midday as the blind is wont to grope in the dark, and not make straight thy ways. And mayst thou at all times suffer wrong, and be oppressed with violence, and mayst thou have no one to deliver thee.

Isaiah 60:2 For behold darkness shall cover the earth, and a mist the people: but the Lord shall arise upon thee, and his glory shall be seen upon thee.

Acts 26:18 To open their eyes, that they may be converted from darkness to light and from the power of Satan to God, that they may receive forgiveness of sins and a lot among the saints, by the faith that is in me.

1 Peter 2:9 But you are a chosen generation, a kingly priesthood, a holy nation, a purchased people: that you may declare his virtues, who hath called you out of darkness into his marvelous light: