John of the Cross spoke of how inner silence of prayer/contemplation provides immunity from attacks from the devil by reducing the imagination and verbal thoughts to tamper with.
(See
Ascent of Mt Carmel Book 3, chapter 4 #1 p 260
“For the devil has no power over the soul unless it be through the operations of its faculties, principally by means of knowledge, whereupon depend almost all the other operations of the other faculties. Wherefore, if the memory be annihilated with respect to them, the devil can do naught; for he finds no foothold, and without a foothold he is powerless.”
and Book 3 Chapter 6, #2 262
"2. In the second place, it is freed from many suggestions, temptations and motions of the devil, which he infuses into the soul by means of
thoughts and ideas, causing it to fall into many impurities and sins, as David says in these words: ‘They have thought and spoken wickedness.’ And
thus, when these thoughts have been completely removed, the devil has naught wherewith to assault the soul by natural means."
ccel.org/ccel/john_cross/ascent.pdf
We all find it extremely difficult to practice silence, outer and inner. Even if we do not speak we usually have that inner monologue going on except in moments of pure attention. It takes faith to get through what seems to be a negative phase befor we realize the more subtle fullness of Christ already there all the time. There are so many distractions.
We often refer to the Letter to the Bishops of the Catholic Church on some aspects of Christian Meditation – but then skip over that it acknowledges:
That does not mean that genuine practices of meditation which come from the Christian East and from the great non-Christian religions, which prove attractive to the man of today who is divided and disoriented, cannot constitute a suitable means of helping the person who prays to come before God with an interior peace, even in the midst of external pressures.
And yet dangers can be anywhere. The letter begins wiht errors in the early Church (cf. 1 Jn 4:3; 1 Tim 1:3-7 and 4:3-4) and “subsequently, two fundamental deviations came to be identified: Pseudognosticism and Messalianism”
Eastern forms do not have the monopoly on dangers. Any time there is the risk of Christ being subordinate to any method, experience or other goal there is danger.
Danger to believe that out own efforts bring our salvation; danger to believe that our faith eliminates any need for effort on our part.
Danger that we stive to extingish our very self through some immersion in the indeterminate abyss; danger also that we place God within the box of our own favorite limiting images. Danger of ego extinction & danger of ego inflation.
Danger that we make our feelings the sole criteria of spiritual progress; danger that we think we have it all figured out intellectually or have the elite knowledge.
Danger to think we can control God’s action by any technique or prayer.
Danger of believing one is God; danger of failing to acknowledge God in others.
Yes, there are many, many dangers everywhere the human heart can wander. The devil wants us to sin. S/He needs our free will for that.