The solemnity of the Most Holy Trinity, also known as Trinity Sunday, is observed on the Sunday following Pentecost.

Saints over time have commented on the importance of the Holy Trinity, speaking on its greatness, simplicity, and power to transform the souls of believers.

To pay tribute to the Holy Trinity, here are 10 illuminating quotes from the mouths, minds, and hearts of 10 different saints:

• St. Augustine: “For to have the fruition of God the Trinity, after whose image we are made, is indeed the fullness of our joy, than which there is no greater.”
• St. Teresa of Ávila: “The three Persons are distinct from one another; a sublime knowledge is infused into the soul, imbuing it with a certainty of the truth that the Three are of one substance, power, and knowledge and are one God.”
• St. Seraphim of Sarov: “In spite of our sinfulness, in spite of the darkness surrounding our souls, the grace of the Holy Spirit, conferred by baptism in the name of the Father and the Son and the Holy Spirit, still shines in our hearts with the inextinguishable light of Christ … and when the sinner turns to the way of repentance the light smooths away every trace of the sins committed, clothing the former sinner in the garments of incorruption, spun of the grace of the Holy Spirit. It is this acquisition of the Holy Spirit about which I have been speaking.”
• St. Patrick (from “St. Patrick’s Breastplate” prayer): “Today I put on a terrible strength invoking the Trinity, confessing the Three with faith in the One as I face my Maker.”
• St. Catherine of Siena: “O Trinity, eternal Trinity! Fire, abyss of love … Was it necessary that you should give even the Holy Trinity as food for souls? You gave us not only your Word through the Redemption and in the Eucharist, but you also gave yourself in the fullness of love for your creature.

• St. Thomas Aquinas: “The Father loves not only the Son but also himself and us, by the Holy Ghost.”
• St. Ambrose: “Rise, you who were lying fast asleep … Rise and hurry to the Church: Here is the Father, here is the Son, here is the Holy Spirit.”
• St. John Paul II: “A great mystery, a mystery of love, an ineffable mystery, before which words must give way to the silence of wonder and worship. A divine mystery that challenges and involves us, because a share in the Trinitarian life was given to us through grace, through the redemptive Incarnation of the Word and the gift of the Holy Spirit.”
• St. Faustina: “When One of the Three Persons communicates with a soul, by the power of that one will, it finds itself united with the Three Persons and is inundated in the happiness flowing from the Most Holy Trinity, the same happiness that nourishes the saints. This same happiness that streams from the Most Holy Trinity makes all creation happy; from it springs that life which vivifies and bestows all life which takes its beginning from him.”
• St. Francis de Sales (from a consecration prayer to the Trinity): “I vow and consecrate to God all that is in me: My memory and my actions to God the Father; My understanding and my words to God the Son; My will and my thoughts to God the Holy Spirit.”