The kingdom belongs to the poor and lowly, which means those who have accepted it with humble hearts. Jesus is sent to "preach good news to the poor"; he declares them blessed, for "theirs is the kingdom of heaven." To them - the "little ones" the Father is pleased to reveal what remains hidden from the wise and the learned. Jesus shares the life of the poor, from the cradle to the cross; he experiences hunger, thirst and privation. Jesus identifies himself with the poor of every kind and makes active love toward them the condition for entering his kingdom.
-- CCC 544