Matt. 5:6 Blessed are those who hunger and thirst for righteousness, For they shall be filled.

What exactly does it mean to hunger and thirst after righteousness?  We know how we feel physically when we have been deprived of food or drink for periods of time, but how does that translate to hungering and thirsting after righteousness?  How will we know that we have tasted righteousness?  Even more basic, what is righteousness?  Indeed, these are difficult questions that we cannot avoid.  We must not only meditate upon them, but it is of necessity that we take action upon them.
Fortunately, Paul provided an answer for at least one of those questions.  In his letter to the church at Rome, Paul wrote:
Rom. 14:17 For the kingdom of God is not meat and drink; but righteousness, and peace, and joy in the Holy Ghost.
The kingdom of God IS righteousness.  Blessed are they who hunger and thirst after righteousness; blessed are they who hunger and thirst after the kingdom of God.  Blessed are they whose spirits yearn to be citizens of the kingdom of God.  Blessed are they who are famished, who are weak from being deprived of the Holy Spirit.  Truly, God will fill them with His Spirit that they may never hunger again.