The Lord addresses his invitation to the thirsty and the poor. The great accomplishment of Thomas Aquinas was that he saw himself as one thirsty and poor. “Blessed are the poor in spirit, for theirs is the kingdom of heaven. . . . Blessed are those who hunger and thirst for holiness, for they shall be satisfied” (Mt 5:3.6). Every official edition of the Roman Missal contains the prayers of Saint Thomas Aquinas to be recited by the priest before and after Mass. These prayers are, I think, a distillation of all that the Angelic Doctor lived and taught. One has only to pray Saint Thomas’ Prayer Before Mass to understand how he saw himself:
I come sick to the physician of life; unclean, to the fountain of mercy; blind, to the light of eternal brightness; poor and needy, to the Lord of heaven and earth. Therefore I ask for the fullness of your infinite bounty, that you would graciously heal my sickness, wash away my uncleanness, enlighten my blindness, enrich my poverty, and clothe my nakedness; so that I may receive the Bread of Angels, the King of kings and Lord of lords, with such reverence and humility, such sorrow and love, such purity and faith, such purpose and intent as shall further my soul’s salvation.
Biography of Saint Thomas, HERE.