The word Rhema is Greek in origin (Strong's Concordance #G4487) and is defined as an utterance (individually, collectively or specifically), by implication a matter or topic. In the Bible, Rhema is many times translated as the word "word." It can be used to refer to Jesus Himself, the messages he gave or the message about him. Its first appearance in the New Testament comes as part of Jesus' response to the devil's temptation that he turn stones into bread (Matthew 4:4). The second place it is found is in Jesus' response in Matthew 12 to some self-righteous religious leaders who stated he cast out demons by the power of Satan himself.
36. But I say to you, for every idle word (Rhema) that men may speak, they shall be held accountable . . . (Matthew 12:36)
Another word in the Greek language, Logos (Strong's Concordance #G3056), can also be translated as "word" in a number of English translations, such as is found in the first chapter of John.
1 In the beginning was the Word (Logos), and the Word (Logos) was with God, and the Word (Logos) was God. (John 1:1)
Some Pentecostal Christians view Rhema as the Holy Spirit's 'voice' that guides a believer. Some Evangelical Christians, however, think that Rhema and Logos are synonymous. Many Charismatic teachers promote the belief that there is a distinct difference between Rhema and Logos even though both are translated as 'word' in English Bibles. They believe that Logos is the Biblical written word. Rhema, on the other hand, is believed to be a special revelation from God. It may come as a realization that a Biblical verse, in spite of its context, applies to a current event or set of circumstances. Guidance on how to live ones life today is pursued through rhema-type words. According to most Greek scholars, however, there is no validity in the argument that the New Testament writers made such a clear distinction between these words in their writings.