The name devil (diabolos – G1228) is defined as slanderer. The Scriptures also refer to the devil as the accuser of the brethren (Revelation 12:10). Jesus tells us that Judas Iscariot was a devil (John 6:70-71), implying that he was a false accuser or a slanderer. Jesus could have meant this to show Judas slandered his enemies, but Jesus may also be implying Judas was slandering Jesus in some manner. Perhaps when Judas was sent out to preach the Gospel (cf. Luke 9:1-2), he may have preached a messiah more to his liking (cf. John 12:34), than what Jesus told him to say. In any case, Jesus revealed in Luke 8:12 that it is the devil who removes the word of God (the ‘seed’ in the parable) from the hearts of men. This attaches a kind of omnipresence to a being other than God, unless it can be shown Jesus doesn’t mean to say an actual spirit being takes the word of God out of the hearts of men. Our modern theology seems to make the Devil, called Satan, into a kind of god who possesses God-like powers, but this is impossible. Only the Lord is God, and no one is able to oppose him.
Certainly Paul claimed that men bearing fruit to the flesh often showed themselves as examples of diabolos (devils) in 1Timothy 3:11 (see also 2Timothy 3:3 and Titus 2:3). In fact Luke records Paul of saying Elymas bar Jesus was a child of the devil (Acts 13:6-10). Here was a man who claimed to be a disciple of Jesus (bar Jesus) who sought to turn away the Roman deputy from the Gospel preached by Paul. Therefore, Paul called him not a ‘son of Jesus’ (bar Jesus), which would make him a son of the Kingdom, but a tare or a son of the devil (Matthew 13:38)!
The fourth Gospel also refers to men who slandered or falsely accused Jesus of wrongdoing and even being a demoniac (John 8:44, 48). This occurred when many began to believe Jesus as he preached in the Temple (John 8:30). When Jesus told the people they would truly be his disciples only if they continued in his word (i.e. applied it to their lives – John 8:31-32), the authorities began to question Jesus’ conclusions (John 8:33), and in challenging Jesus, they sought to remove the word of God (the ‘seed’ in the Parable of the Sower – Luke 8:11) from the hearts of those who were just beginning to believe.
In the Parable of the Sower, the enemies of the Gospel are personified in the single word diabolos (G1228), and the translator renders this as “the devil”. The problem is this is often interpreted literally. The seed in the parable isn’t to be taken literally, but actually refers to the word of God. The type of ground isn’t to be taken literally. Rather, it refers to the hearts of men. Neither the terms: wayside, birds, rocks, thorns or even good ground are to be taken literally, but all have their respective meaning. Nevertheless, one may conclude that, because the birds in the parable refer to “the devil”, then the devil should be at least as literal as the word of God and the hearts of men in the parable. What can we say about this?
Both Matthew and Mark have their own versions of the Parable of the Sower. In their versions the birds are defined as the evil one (Matthew 13:19) and Satan (Mark 4:15), showing that whatever Jesus actually said in the parable, he either repeated slightly different versions on a number of occasions, or the Gospel writers are given at least a limited amount of freedom of expression, while recording Jesus’ words and what he did for the encouragement and training of his disciples. All three of the Synoptics place the parable near the time of Jesus being called a demonic. Matthew and Mark place the parable just after that event, but Luke places it just before the slanderous remark. The point is not whether the remark comes before or afterward, but, rather, that it a slanderous, false accusation (a diabolos – G1228) that either precipitated the parable (Matthew and Mark) or interprets the parable (Luke).
No matter how we define devil in Luke 8:12, it must be conceded that it was men during Jesus’ ministry who actually slandered him or were his false accusers. It was really men whom the Scriptures place in positions to actually remove the word of God from men’s hearts, just after Jesus preached to them. It is actually men who are everywhere, whether with Jesus (cf. Mark 3:22), or with Peter (Acts 5:1-10; 12:1-11) or Paul (Acts 13:6-10, 45-50). The Scriptures never show or even imply that a spirit being other than God has omnipresence. No spirit being (except God) is able to be in more than one place at any given moment. If the devil, mentioned in Luke 8:12 represents a spirit being, how is he able to do what the Scriptures claim he cannot do, and why don’t the Scriptures clearly show this spirit being exercising such Godlike powers? We need to keep in mind that our interpretations should never go beyond what the Scriptures actually say (1Corinthians 4:6; cf. 2John 1:9).
 See my previous study: God and Dualism