Blessed are the poor in Spirit
Blessed are they that mourn
Blessed are the meek
Blessed Are They Which Do Hunger and Thirst after Righteousness
Blessed are the merciful
Blessed are the pure in heart
Blessed are the Meek: Meekness is a great thing to be a holder of. Those who are meek are willing to learn, to be taught the word of God and to come unto Christ. They are humble individuals with a desire to know the Lord's will. People who are meek are calm spirited and are able to see things as they are, because their emotions do not override what is being taught, etc.
Blessed are the poor in Spirit: Those who are poor in Spirit have a great desire to come where they will be fed and clothed. They have probably had battles and are now humble, wanting to learn and to become a part of something better and more worthy in life. They are seekers of truth. They are not prideful, boastful, or of any such thing, they come knowing that they may have little to offer.
Blessed are the pure in heart: This is an important attribute, as the pure heart is untainted by worldly desires and anger/malice. No one is perfectly pure in heart, but it is something that we can work on and strive to be as we push out the bad things that lay in our heart, we give room to more beautiful and virtuous things.