On my opinion, you are reading too much into it.

"Divine life" is not a precise expression, as far as I know. 

All the same, who is this Fr. Molinie? Is this a new book or an old work with a pre-conciliar imprimatur (which is not always a guarantee or orthodoxy. There were cripto-Modernists way before the 1960s)?

I am not an expert in Theology, but I always believed that most of the holy saints would not dare to declare that they had the certitude of going to heaven. ..Except Fatima seers and rare cases. St Bernadette knew, but only because of privileged graces from Our Lady. St. Paul too.
We normally hear that we must work out our salvation in fear and trembling...till our last Brrreath!

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https://catholiccandle.org/2024/04/10/in-case-you-missed-it-april-2024/#_ftn2
Two excerpts/ publications:

"... Recently, The “new” liberal SSPX taught (heretically[2]) that we are all, always, unchangeably, in the state of Sanctifying Grace.  Here are the N-SSPX’s words: 

What never changes, no matter the state of things [is that] the divine life is in us.[3]
This statement is heretical for two reasons: 
v  First, it is false to claim that everyone possesses Sanctifying Grace – i.e., that the Divine Life Itself is within everyone – for the majority of men do not possess it.
 
v  Second, it is false to claim that for those who at one time possessed grace, this possession “never changes, no matter the state of things”, as if this Divine Life could never be lost.
Many, even of those who call themselves “traditional Catholics”, vacillate between the state of grace and the state of mortal sin, whereas, the N-SSPX says that “what never changes” is that grace, “the divine life”, is in us.
This N-SSPX teaching promotes universal salvation.  But it should not surprise us that the “new” SSPX promotes universal salvation, since that group promotes the vice of presumption in these words:
The virtue of hope gives us this certitude … we will see our God, that we will possess Him and willl [sic] be united to Him forever.
In other words, the “new” SSPX says Hope makes us sure we will go to heaven.[4]  Faithful and informed Catholics know that this is not the description of the Virtue of Hope but rather of the vice of presumption.

Conclusion: Let us fulfil our duty to regularly study our Catholic Faith.  Let us stay away from the “new” S...."

*****

 
[3]          Here is the full quote, which is an ad for a book which the Angelus Press is selling:
 
The Courage to Be Afraid is remarkably different from other spiritual books.  It is a tour de force that examines many aspects of the Christian life, yet, always returning to a simple, powerful theme: we have to let God act.  Fr. Molinie addresses himself to us, children of the modern world, in order to recall us forcefully to what never changes, no matter the state of things: the divine life is in us, and will transform us if we surrender to it.  “God’s love is a consuming fire”.
 
Quoted from the Angelus Press sales flyer sent to its mailing list about February 20, 2024 (emphasis added).

I don't know anything about this particular statement but the Angelus has put up different quotes from that book on my YouTube feed and I remember thinking that book seemed novus ordo like and too sentimental. 

I don't know anything about this particular statement but the Angelus has put up different quotes from that book on my YouTube feed and I remember thinking that book seemed novus ordo like and too sentimental.

About the OP link: that is Catholic Candle web page, not my comments. I am still neutral about this priest, or his background. 
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https://www.radio-en-ligne.fr/podcasts/le-cure-dars-et-vatican-ii-par-le-pere-marie-dominique-molinie-op

I've been researching this priest ( He was born May 29, 1918, died June 15, 2002 AD at Perpignan.) yesterday and today, my computer is constantly updating, plus I have weak internet. Anyway, There are seven Talks of his , in French, on the above link: that link has tons of ads...like Fox News!!

These were recorded in 1979, during a retreat at: Foyer de charite de Baye. So honestly I can't guess if he is Trad, simply because I haven't been able to listen much. He does say that the Eucharist and Thanksgiving, they are the same thing...Hmmm  He is all for Gallicanism.  He quoted St Cure of Ars and is wellread about most of the saint's sayings and writings and supernatural aura and gifts.
He only read the Vatican II docuмents around 1978, and mentions that Lumen Gentium and Dei Verbum brushes against long standing Church teaching...If someone isn't happy with these, well, these dogmatic Constitutions modified other docuмents, so if they can modify, well just be patient and then maybe someday these could be modified as well.
He introduces his week long retreat conference theme: St. Cure d"Ars and Vatican II.  He was going to focus on St John Vianney's idea of Hell, and Vatican II's attitude towards hell.
Two days later a religious Brother asks him to change the topic and talk rather about:
" "Comment faire pour atteindre les jours ou on brule d'amour?" Translated: What must we do to attain those days where we burn out of love.." So looks like he shifted the theme!!?
He is a joy to listen to, 7 talks about 30 minutes each. "We are as blocks of wood, really cold wood (little spiritual  desire for God, selfish, sinners etc.). ONLY God can create a fire...He is the match (so to speak) and He will decide if and when to inflame you. A block cannot move, so if the lighted match is 5" away, the wood will not ignite. There is nothing you can do. Only God can move the match closer, there is nothing to do but wait."
That's the flavor of his talks...
I'll keep you posted next Friday.
If someone else could listen to the talks on high speed internet, and make a sort of report, that would be great. PV...where are you?