The only difference between these two verses and the same-numbered verses in Matthew 5 is the New World emphasis on written scripture rather than oral learning that was a feature of the Matthean Sermon.
Similar to the amplification of the commandment that we should not commit murder, the commandment against adultery is shifted from the sin of the accomplished fact to the desire that might lead to the attempt. As with the amplification of the commandment on murder, the emphasis shifts from the victim to the perpetrator as the location of the problem. This is not to say that Jesus did not have sympathy for victims, but rather than he was concerned for all souls, and particularly those whose hearts had become so hardened that they might even consider some of these heinous crimes.