(ubi Sup.) There are some who both experience its usefulness and feel a desire for it, but some of them the calamities of this world frighten, and others its prosperity allures, so that they do not attain to that which they approve. Of the first of whom He says, And these are they who fell on stony ground; of the latter, And these are they which are sown among thorns. But riches are called thorns, because they tear the soul with the piercing of its own thoughts, and after bringing it to sin, they, as one may say, make it bleed by inflicting a wound. Again He says, And the toil of this world, and the deceitfulness of riches; for the man who is deceived by an empty desire of riches must soon be afflicted by the toils of continual cares. He adds, And the lusts of other things; because, whosoever despises the commandments of God, and wanders away lustfully seeking other things, is unable to attain to the joy of beatitude. And concupiscences of this sort choke the word, because they do not allow a good desire to enter into the heart, and, as it were, stifle the entrance of vital breath. There are, however, excepted from these different classes of men, the Gentiles who do not even have grace to hear the words of life.
Source: Catena Aurea by Aquinas