Daf Yomi - Beitzah 13 - Holy thoughts

The Gemara states that one can separate both Terumah Gedolah and Terumas Maaser with a thought and one does not need to physically or orally designate the terumah. There are certain mitzvos which require one to contemplate the mitzvah, such as loving HaShem, fearing HaShem and other such mitzvos. There is even a situation where if one sought to perform a mitzvah and he could not complete it because of extenuating circumstances, it is considered as if he performed the mitzvah. Thus, thoughts play an important part in serving HaShem. Rav Chaim Volozhiner writes in Nefesh HaChaim that one who entertains immoral thoughts is worse than the Roman general Titus, who defiled the Holy of Holies, because a gentile does not have the capability of reaching high spiritual levels, whereas a Jew has the ability to reach very high spiritual levels, and improper thoughts defile the spiritual Holy of Holies. This idea should teach us that not only do we have to be pure in our actions but we must also keep our thoughts pure and holy.