The psalmist both hates and abhors lying. Lying is deceit; it is making a thing seem to be true but is based upon no truth at all. The difference between "hate" and "abhor" is mainly in the degree of its effect. To hate lying may be enough, but to abhor it seems to indicate that a purposeful decision has been made in one's mind to always meet lying with the attitude that it is fraud. I am sure every believer should decide early in life to both hate and abhor lying, because lying is an action that all of us do, and God is not pleased with it.
Once a believer has decided to hate and abhor lying, it is imperative that he replace that hate with something that he loves; otherwise his hate for lying may turn again to love for lying depending upon the situation. But, if a believer replaces love or acceptance of lying with another love, his hate for lying may become more consistent and perhaps even permanent.
So, the psalmist replaced his love or acceptance for lying with the love of God's law. Today we accept the sixty-six books of God's word as God's law. We should, then, fall in love with God's word and spend much time in it. The word of God will change our lives in many ways, but one of the main ways is to turn our love for sin to a love of God and His word and to give us confidence in the truth of God's word, denying and repelling the philosophy of the world, which is the opposite, many time, of the truth of God.