1. St. John Chrysostom

"When the Eucharist is being celebrated, the sanctuary is filled with countless angels who adore the divine victim immolated on the altar." 

2. St. Augustine

"The angels surround and help the priest when he is celebrating Mass."

3. St. John Bosco

"The best time to ask and obtain favors from God is the time of the Elevation of the Host." 

4. St. Thomas Aquinas

"The celebration of Holy Mass is as valuable as the death of Jesus on the cross." 

5. St. Teresa

She was overwhelmed with God’s Goodness and asked Our Lord “How can I thank you?” Our Lord replied, “ATTEND ONE MASS.”

6. Our Lady to Blessed Alan

“My Son so loves those who assist at the Holy Sacrifice of the Mass that, if it were necessary He would die for them as many times as they’ve heard Masses.” 

7. St. Jean Vianney

"When we receive Holy Communion, we experience something extraordinary – a joy, a fragrance, a well-being that thrills the whole body and causes it to exalt." 

8. St. Jean Vianney

"There is nothing so great as the Eucharist. If God had something more precious, He would have given it to us."

9. St. Don Bosco

"Be eager to go to Mass on weekdays also, even if it costs a sacrifice. Our Lord will reward you with His Blessings and make you succeed in your undertakings." 

10. St. Jean Vianney

"When we have been to Holy Communion, the balm of love envelops the soul as the flower envelops the bee."

11. St. Pio of Pietrelcina

"It would be easier for the world to survive without the sun than to do without Holy Mass."

12. St. Jean Vianney

"If we really understood the Mass, we would die of joy."

13. St. Thomas Aquinas

"Communion is the source of life and fountain of grace. It forgives venial sin and weakens the hold of selfish desires. It strengthens the weak, restores health to the sick, increased virtue, makes grace abound, purges away vices and refreshes the soul."

14. St. Alphonsus

"Jesus remains day and night on our altars that he may be easily found and that he may bestow favors on everyone."

15. St. John Vianney

"How great we are to be nourished by the flesh of a God. The body of those who frequently make very devout Communions will enjoy a special glory in heaven."

From my articles on Catholic365.com