The three steps are the purgative way, the illuminative way, and the unitive way. One step must be passed through to get to the next. So to get to the illuminative way you must first pass through the purgative way, but let me tell you what is involved in each step first.
To get into the purgative way you must either convert and become Catholic or if you are a Catholic in Mortal Sin, you must go to Confession. You can’t grow in holiness toward God if you are enemies with Him.
In brief, the whole idea behind the purgative way is to turn away from Mortal Sin and begin growing in virtue toward God - it is putting to death the deeds of the flesh (Romans 8:13). There is a second conversion spoken of as a transition from the purgative to the illuminative way through a kind of Dark Night of the senses, meaning less warm fuzzy feelings, external consolations, when you pray and just throughout your day. In the illuminative way, you are focused more on developing virtues and weeding out the venial sins in your life. Finally, there is another transition from the illuminative to the unitive way through a Dark Night of the Spirit where it feels like the soul has been abandoned by God completely. Yet, the unitive way has been described as Heaven on earth.
Some scriptures that point to these three ways are as follows:
Psalm 34:14 Depart from evil, and do good; Seek peace, and pursue it.
- Depart from evil is done in the Purgative Way.
- Do Good is done in the Illuminative Way.
- Seek peace, and pursue it is done in the Unitive Way.
Luke 9:23 And He [Jesus] was saying to them all, "If anyone wishes to come after Me, let him deny himself, and take up his cross daily, and follow Me.
Also some spiritual giants such as St. Thomas Aquinas have pointed to the three writings of Solomon as each pointing to one of the ways. The books of Solomon are Proverbs, Ecclesiastes, and the Song of Solomon.
In the book of Proverbs, it talks about two ways - one that leads to life and one that leads to the grave. Proverbs is describing someone who might be tempted to leave Wisdom behind all together and fall back into Mortal Sin.
Ecclesiastes reflects the attitude of those in the illuminative way. Seeing that all things here on earth are vanity. That the only thing that matters is, in fact, God.
Finally, in the Song of Solomon it talks about the relationship between two lovers. Spiritually speaking, this is about the relationship between God and a soul. Many great saints would point to this book in the Bible as the crown of the spiritual life.
Some have seen the Tabernacle that Moses built in the wilderness as a type of model to the spiritual life.
The tabernacle had three parts: the court, the Holy Place and the Holy of Holies.
In the court were two things: a bronze Laver and an altar for burnt offerings. The Holy Place had three things: a lamp stand, an altar of incense, and a table with the bread of the presence. Finally, in the Holy of Holies was the Ark of the Covenant, God's dwelling place.
Here is a spiritual interpretation on these three places:
- In the court is where you would wash in Baptism in the Laver and then put to death the deeds of the body. That is what all of those animal sacrifices represented, and points us to the purgative way.
- In the Holy Place is where we find more fulfillment in the sacrament of the Eucharist, prayer, represented by the incense, and the gifts of the Holy Spirit, represented by the lamp stand.
- Finally, in the Holy of Holies we see God as He is face to face. We no longer love Him out of fear. We no longer love Him because of what He gives us. It is here that we love Him for Himself.
St. Teresa of Avila compares the spiritual journey to a Mansion with many rooms of which we must pass through to get to the epicenter, where we meet God in His Majesty.
St. John of the Cross compares it to climbing a mountain.
St. Catherine of Sienna compares it to kissing the wounds of Christ’s feet, then His wounded side, and then, finally, His mouth.
Introduction to the Devout Life - by St. Fancis DeSales
The Soul of the Apostolate - by Dom Jean-Baptiste Chautard
The Three Conversions in the Spiritual Life
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