Garrigou-Lagrange quotes several of the saints regarding this, but here is only a few examples. I use these paragraphs to show the consistency of these saints who share their journeys with us. Many of my readers have expressed that they understand these stages. Perhaps this section will help. I am writing about this as many people get to this stage but then pull back. Do not pull back. The note on Tauler is so true. The void can only be filled by Christ Himself.
The last section is most beautiful. Like any lover, who wants to be united with the beloved and become one with him, so too, we enter in that daily desire for oneness and unity. I pray daily to be taken up into Christ and to become one with Him.
Is there anything else more worthy of our prayers than this desire?
Hugh of St. Victor had compared the passive purification of the soul by grace and the love of God to the transformation which green wood undergoes when attacked by fire: "The dampness is consumed, the smoke diminishes, the victorious flame shows itself; . . . finally it communicates its own nature to the wood, which is set completely on fire. Likewise the love of God gradually grows in the soul, the passions of the heart at first resist, which causes many sufferings and troubles; this thick smoke must be dissipated. Then the love of God becomes more ardent, its flame more lively. . . and finally it penetrates the entire soul. The divine truth is found and assimilated by contemplation; the soul, detached from self, no longer seeks anything but God. He is for it all in all; it rests in His love and finds therein joy and peace. (11)
Speaking in like terms, Tauler says that the Holy Ghost creates a void in the depth of our souls where egoism and pride still dwell. He creates the void that He may heal us, and then He fills it to overflowing while continually increasing our capacity to receive.(12)
St. Teresa speaks of the passive purification of the spirit in the first chapter of the sixth mansion of The Interior Castle.
We read also in the life of St. Vincent de Paul that for four years he endured a trial of this type, which was marked by a persistent temptation against faith. The temptation was so strong that he wrote the Credo on a sheet of paper, which he carried over his heart and pressed from time to time to assure himself that he did not consent to the temptation.(13)
We should also keep in mind that St. John of the Cross, after Tauler, describes this state as it is in the saints in all its amplitude and intensity, such as he himself must have undergone it. But the purification is found in lesser degrees and under less purely contemplative forms, united, for example, to the great trials met with in the apostolate.
If the passive purification of the spirit seems extraordinary to us outside the normal way of sanctity, this is because we do not give enough thought to what a profound purification of the soul is necessary to receive immediately eternal life, the beatific vision of the divine essence, without having to pass through purgatory or after having done so. And when we read the exposition of this doctrine in the great masters, we read it perhaps through a certain curiosity about divine things, but without a sufficiently sincere desire for our own sanctification. If we had this desire, we would find in these pages what is suitable for us, we would see there the one thing necessary.
We must in one way or another pass through this crucible in order to have a concept of our Savior's passion, of the humility of Jesus and His love for us, that will not be only a confused concept, or only a theoretically distinct concept, but an experimental concept, without which there is no love of the cross or true sanctity.
We must tell ourselves that the world is full of crosses that have unfortunately been lost like that of the bad thief. God grant that our sufferings may not be fruitless and that our crosses may resemble that of the good thief, which served as a reparation for his sins. May our crosses resemble even more closely the cross of Jesus and configure us to Him. Sanctifying grace, as it grows, makes us more and more like to God; inasmuch as it is Christian grace, it assimilates us to Christ crucified, and should make us grow more like Him until our entrance into heaven. It should mark us with the likeness of our Savior who died for love of us.