One of the images that Scripture gives of a life of sin is that of fruitlessness, as represented by the word akarpos. The seed that is planted among the thorns, those thorns being the cares of this world and the deceitfulness of riches, is choked out and becomes unfruitful (Matt. 13:22). Jesus uses the same word in the record that Mark gives us of this parable (Mark 4:19).
St. Paul says that if a man prays in a tongue without interpretation, then his understanding is unfruitful (1 Cor. 14:14).
In Ephesian 5:11, Paul also tells us to have no fellowship with the “unfruitful works of darkness, but rather reprove them.” He also wants believers to learn how to maintain their good works, in order to avoid being unfruitful (Tit. 3:14). If believers grow in grace and holiness, then the result will be that they are not barren or unfruitful in the knowledge of the Lord Jesus (2 Pet. 1:8). And in Jude 12, the false teachers are described in many ways, but one of the central features of their lives is that they are “without fruit” (the same word akarpos is used here).
This striking biblical image is a good example of sins of omission. These settings are not describing the presence of evil fruit, but rather the absence of good fruit. We are responsible for what we do not grow.