Throughout the remainder of this chapter, most of the verbs are in the aorist tense, but the aorist does not necessarily indicate past time, and a past tense in English may imply that the action described has ceased. The force of the Greek aorist in this context is to indicate that these actions are typical of what men have done at all times throughout history; for the English reader the present tense is more natural in expressing such events. This is why throughout this passage the Good News Translation uses the present tense, rather than the past tense, as most translations do.
They know God in Greek is actually a participle indicating concession, that is, “even though they know God” (see Revised Standard Version). However, a number of translations do as the Good News Translation does, and renders this by a finite verb (see Jerusalem Bible “they knew God”). The knowledge referred to here is the recognition of God’s existence, not the knowledge of a personal relationship with God. It is important in the selection of a term for know to indicate that this is knowledge about and not intimate relationship with. In some instances, therefore, one must employ a translation such as “they know about God” or “they are acquainted with who God is.”
They do not give him the honor that belongs to him is rendered in the New English Bible by a more literal translation: “they have refused to honor him as God.” In order to express the meaning of this clause appropriately, it may be necessary to say: “they refused to honor God as the one whom they really know he is” or “they refused to honor God; they did not say to him, You truly are God.”
The clause nor do they thank him must be rendered in some languages as “and they do not say thank you to God” or “their hearts are not thankful for what God has done.”
The verb rendered become complete nonsense occurs only here in the New Testament; the corresponding adjective occurs in a similar passage in 1 Corinthians 3.20 (“the thoughts of the wise are worthless”) and elsewhere. Most translations render this phrase something like “they became futile in their thinking” (Revised Standard Version). In languages in which thoughts is much more normally expressed as a verb, it may be necessary to restructure this clause as “when they think, they think nothing,” “when they think, it has no value at all,” or “they think complete foolishness.”
Their empty minds is literally “their senseless heart.” In such a context in English it is much more natural to use a plural rather than a singular, and for this reason the Good News Translation uses the plural minds. Also, as is so often the case in the Bible, “heart” refers to the intellectual rather than the emotional capacity of the individual. The adjective rendered here empty means “stupid” or “without understanding” (see Matthew 15.16; Mark 7.18; Romans 1.31; 10.19). It is not easy to find an appropriate equivalent expression for this last clause of verse 21. In some languages the closest equivalent may be “their minds are empty, and their thoughts are dark,” “since their minds are empty, they think only dark thoughts”, or even “darkness covers (or fills) their empty minds.” The attributive “dark” as a qualifier of “thoughts” does not refer to ignorance but to failure to think right or correctly about moral issues. Therefore one can translate as “they do not think as they should,” “they do not think right,” or even “their thoughts are all wrong.” Terms such as “not right” or “wrong” should imply moral inadequacy, not simply technical incorrectness.
Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on Paul’s Letter to the Romans. (UBS Handbook Series). New York: UBS, 1973. For this and other handbooks for translators see here .