21 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. (Romans 1:21 KJV)
William Burkitt’s Commentary
From this verse to the end of the chapter, we have a large and black catalogue of the sins which the old Heathens or Gentiles were guilty of; some of which they voluntarily committed, and others were judiciously delivered up to (for God, without any impeachment of his holiness, often punishes sin with sin.) Their sins voluntarily committed are here recited and the first of them is their sinning against light and knowledge. They had some natural notices of God implanted and imprinted in their minds, and such an additional knowledge of his being and attribute, as might be gained by an attentive study in the book of the creatures; but they rebelled against this light, and thereby contracted an aggravated guilt.
Learn thence, that to sin against light and knowledge, either in the omission of duty or commission of sin is the highest aggravation of sinfulness: As ignorance lessens, so knowledge aggravates the malignity of sin.
The next sin charged upon them was, they did not glorify that God whom they had the knowledge of: That is, they did not conceive of him and worship him as became his divine perfections and excellencies; they did not esteem so high of him as they ought and pay that homage and honour to the Deity which they should.
Learn thence, That the knowledge which we have of God and his attributes, if it does not engage us to honour, glorify, and worship him, suitable to his adorable perfections, it is vain and useless in God’s account and will but expose us to a more dreadful condemnation.
Another sin mentioned in this verse, which the Heathens were guilty of, was the sin of unthankfulness. They glorified him not as God, neither were they thankful: That is, they had not a due sense of the favours and benefits of God conferred upon them; but, ascribing the blessings of heaven to chance and fortune, to fate and destiny, to the influence of the stars and planets, to their own prudence and providence, they paid their thanks to blind fortune, for a favour which the eye of providence had bestowed upon them: It is impossible that God should receive the tribute of thankfulness if we do not see all our mercies flowing from him.
Observe further, the sad effect, fruit and consequence of the aforementioned sins. The Heathens which committed them, it is said,
1. That they became vain in their imaginations. That is, they had various opinions and vain conceptions of the Godhead. Some of them denied that there was a God, others doubted whether there was a God or not; some affirmed there was but one God, others owned a plurality, yea, a multiplicity of gods. Some acknowledge God’s being, but denied his providence; others owned his providence, but confined it in its exercise to secondary causes. Thus vain in their imaginations, thus absorbed in their notions, and thus sottish in their reasonings were the Heathens concerning God, his nature and worship. Well might our apostle say, They became vain in their imaginations.
And, 2. That their foolish hearts were darkened: That is, for rebelling against the light received, their minds and understanding were more and more darkened; their natural reason obscured, but because not improved.
Lord, how dangerous is it not to improve our knowledge! how fatal to rebel against the light and convictions of our own minds! It provokes you to deliver us up to the power of spiritual darkness on earth and consigns us over to eternal darkness in hell where is reserved the blackness of darkness forever as the punishment and portion of those that rebel against the light and sin against knowledge.