Why should Tehillim help? Does Hashem really change His mind?… You will find in the chassidut from the Baal Shem Tov the classical explanation that Hashem does not change His mind. When we pray to Hashem… we are actually changing ourselves. It is changing us and when we change we are no longer the same individual upon whom there was a decree, God forbid, that we are trying to annul and cancel…

As a result of our intense prayers to Hashem… Hashem says, ‘You have prayed so much to me you have done so much teshuva [repentance of what we have done wrong and strong desire to return to Hashem’s path], you’ve become a different person, then your mazal has changed as well.’

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Tehillim and prayer can only help if they are accompanied by the proper teshuva, the sincerity, the repentance otherwise a person is just saying words.

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Can we say Tehillim in other languages? Yes, as long as you understand that language… If you say it in Hebrew even if you don’t understand it, it is powerful.