Source: https://www.bertha-dudde.org/en/proclamation/8835
8835 About speaking in tongues....
August 2, 1964: Book 93
You should educate your fellow human beings in all truthfulness, and therefore you first have to receive the truth from Me. I have told you many times already that the truth will bring you enlightenment, that you will not stay in the dark, that you will be able to understand everything. And thus you are given an explanation about the various 'gifts of the spirit', which you can even notice yourselves in those who possess them. You will have to admit that unusual abilities exist when a person has the gift of healing the sick.... you will not be able to deny the gift of prophesy either.... just as remarkable knowledge will be obvious to you too.... They are all things which are unusual in people, powers are manifesting themselves in a person which are undeniably divine activities for the benefit of the souls. But you ask Me in particular about the 'gift of speaking in tongues'.... You have already received the simple explanation from Me that this gift is a special sign of a most heartfelt bond with Me, explained such that I speak through a person who talks to people of different nations and they hear him in their native tongue, so that everyone believes that he speaks to them in their own language. This gift is a most obvious sign of My working.... just like the 'outpouring of My spirit' upon My disciples.... when all people present heard them speak in their mother tongue.... Thus they were speaking in 'foreign tongues'.... and not that a person speaks an incomprehensible language and then believes to be permeated by 'My spirit'.... This is a complete misinterpretation of the Scriptures which certainly speak of the blessed feeling of an inner bond with Me which motivates a person to praise My Being, but it takes place in quiet prayer uttered by the tongue.... and not by the mouth.
I ask you in all seriousness: what point would there be in a prayer articulated with the mouth in an incomprehensible language, if it needs interpreting?.... Am I Myself not able to speak to you in a clearly intelligible way? I want to give you light.... why should I use an interpreter who first has to be enlightened by My Spirit in order to be able to give you light. I Am an unambiguous and true God, and I really have no reason to offer you a muddle of words which needs to be translated by another person. Especially this portrayal of speaking in tongues encouraged people to seek this gift desperately, and thus sects arose whose members assemble as the Pentecostal community in order to acquire this gift due to wrong understanding.... Whenever I speak to people I will always give them light, but I do not speak to those who express themselves confusingly and need an interpreter, who is equally incapable of spreading light. I ask you, why should I speak to you in a language you don't understand? You misunderstand the words in the Scriptures, as far as they can be regarded as My Word.... for even the 'letter' added to My Gospel contains errors. Words have been added which were (are) not 'My Word' and even those are misinterpreted by you, and thus you cannot escape from error. But precisely these words form the basic teachings of those supposedly permeated by the 'spirit of Pentecost'.... And they confuse people because they do not rely on the pure truth which I Myself convey to earth, in fact, they are hostile to it.... They do not accept this pure teaching and this, in itself, should already be evidence for you that they have founded themselves on wrong principles. Anyone who is so convinced of their permeation by My spirit that he speaks in 'foreign tongues' also has to be able to translate it himself in spirit and in truth, since it is not My will to confuse people's spirit but to enlighten it. And this translation has to agree with the spiritual knowledge which I convey to earth from above, or you can reject it as error. I will give light to all of you, and you should not resist this light, for the gift of grace offered to you from above is immeasurable, and yet the error is equally enormous so that I have to be active Myself in order to help you become enlightened again.... And blessed is he who accepts the light that shines for him....
Amen
Translated by Heidi Hanna