Why is this day thus named?
Because on this day the Church blesses ashes, and places them on the heads of her faithful children, saying: "Remember man, thou art dust, and unto dust thou shaft return."
Why is this done?
St. Charles Borromeo gives us the following reasons for this practice: that the faithful may be moved to sincere humility of heart; that the heavenly blessing may descend upon them, by which they, being really penitent, will weep with their whole soul for their sins, remembering how earth was cursed because of sin, and that we have all to return to dust; that strength to do true penance may be given the body, and that our soul may be endowed with divine grace to persevere in penance.
With such thoughts let the ashes be put upon your head, while you ask in all humility and with a contrite heart, for God’s mercy and grace.
Is the practice of putting ashes upon our heads pleasing to God?
It is, for God Himself commanded the Israelites to put ashes on their heads for a sign of repentance. (Jer. XXV. 34.) Thus did David (Ps, CI. 10.) who even strewed ashes on his bread; the Ninivites, (Jonas III. 5.) Judith, (Jud, IX. 1.) Mardochai, (Esth. IV 1.) Job, (JobXLII. 6.) etc. The Christians of the earliest times followed this practice as often as they did public penance for their sins.
Why from this day until the end of Lent are the altars draped in violet?
Because, as has been already said, the holy season of Lent is a time of sorrow and penance for sin, and the Church desires externally to demonstrate by the violet with which she drapes the altar, by the violet vestments worn by the priests, and by the cessation of the organ and festive singing, that we in quiet mourning are bewailing our sins; and to still further impress the spirit of penance upon us, there is usually only a simple crucifix or a picture of Christ's passion, left visible upon the altar, and devoutly meditating upon it, the heart is mostly prepared for contrition.
In the Introit of this day's Mass the Church uses the following words to make known her zeal for penance, and to move
INTROIT God to mercy: Thou hast mercy upon all, O Lord, and hatest none of the things which Thou hast made, winking at the sins of men for the sake of repentance, and sparing them; for thou art the Lord our God. (Wisd. XI. 24. 25.) Have mercy on me, O God, have mercy on me; for my soul trusteth in thee. (Ps. LVI. 2.) Glory be to the Father, etc.
COLLECT Grant to thy faithful, O Lord, that they may begin the venerable solemnities of fasting with suitable piety, and perform them with tranquil devotion. Through Jesus Christ, our Lord, etc.
LESSON (Joel II. 12-19) Thus with the Lord: Be converted to me with all your heart, in fasting, and in weeping, and in mourning. And rend your hearts and not your garments, and turn to the Lord your God; for he is gracious and merciful, patient and rich in mercy, and ready to repent of the evil. Who knoweth but he will return, and forgive, anal leave a blessing behind him, sacrifice and libation to the Lord your God? Blow the trumpet in Sion: sanctify a fast; call a solemn assembly; gather together the people; sanctify the Church; assemble the ancients; gather together the little ones, and them that suck at the breasts; let the bridegroom go forth from his bed, and the bride out of her bride-chamber. Between the porch and the altar the priests, the Lord's ministers, shall weep; and shall say: Spare, O Lord, spare thy people; and give not thine inheritance to reproach, that the heathens should rule over them. Why should they say among the nations: Where is their God? The Lord hath been zealous for his land, and hath spared his people. And the Lord answered, and said to his people: Behold, I will send you corn, and wine, and oil, and you shall be filled with them; and I will no more make you a reproach among the nations, with the Lord Almighty.
EXPLANATION The Prophet Joel exhorts the Jews to sorrow and penance for their sins, that they evade the expected judgment to be sent by God upon the city of Jerusalem. He required of them to show their repentance not merely by rending their garments, a sign of mourning with the Jews, but by a truly contrite heart. The Church wishes us to see plainly from this lesson of the prophet what qualities our penance should possess, if we desire reconciliation with God, forgiveness of our sins, and deliverance at the Last Day, which qualities are not merely abstinence from food and amusements, but the practice of real mortification of our evil inclinations, thus becoming with our whole heart converted to God.
GOSPEL (Matt. VI. 16-21) At that time, Jesus said to his disciples: When you fast, be not as the hypocrites, sad. For they disfigure their faces, that they may appear unto men to fast. Amen I say to you, they have received their reward. But thou, when thou fastest, anoint thy head and wash thy face, that thou appear not to men to fast, but to thy Father who is in secret, and thy Father who seeth in secret will repay thee. Lay not up to yourselves treasures on earth, where the rust and moth consume, and where thieves break through and steal. But lay up to yourselves treasures in heaven, where neither the rust nor moth doth consume, and where thieves do not break through nor steal. For where thy treasure is, there is thy heart also.
EXPLANATION Jesus forbids us to seek the praises of men when performing good works, (fasting is a good work,) and still worse it would be to do good as the Pharisees, through hypocrisy. He also warns us against avarice and the desire for temporal riches, urging us to employ our temporal goods, in giving alms, and doing works of charity, thus laying up treasures in heaven, which are there rewarded and will last there forever. "What folly", says St. Chrysostom, "to leave our goods where we cannot stay, instead of sending them before us where we are going — to heaven!"'
-- Goffine's Devout Instructions