To add a little bit:
This sentence (in Hebrew: ותשובה ותפלה וצדקה מעבירין את רוע הגזרה, uteshuva utefila utzedaqa ma'avirin et roa' hagezeira) is from the well-known piyyut (liturgical poem) Unetaneh Tokef, which is recited during the High Holidays. It is attributed (probably apocryphally) to a certain 11th-century rabbi, Amnon of Mainz but is probably a few centuries older than that.
The sentence from Unetaneh Tokef, which has been translated in the other answers, draws on the language of Genesis Rabba (an early midrashic compilation) 44:15, where it says:
ר' יודן בשם ר' אלעזר אמר: שלושה דברים מבטלין גזירות רעות, ואלו הם:
תפלה וצדקה ותשובה.
Rabbi Yudan said in the name of R. El'azar: three things annul [mevatlin] evil decrees, and they are: prayer, charity, and repentance.
Ma'avirin, the word used in Unetaneh Tokef, is closer in meaning to "averting" or "shifting", which "mevatlin" is like "annulling" or "canceling", but I couldn't give you a good answer as to why the poet chose to use one word over the other. Hope this clarifies this beautiful sentence for you.