In a similar vein, the pasuk in Tehillim (91:7) states: ‘A thousand will be stationed at your side, and ten thousand at your right hand.’ The Ye’aros Devash (Chelek 1, Drush 16) writes that ‘left’ refers to learning Torah shelo l’shma, while ‘right’ refers to learning Torah l’shma.
Accordingly, the pasuk is saying that even if one learns Torah shelo l’shma, he will still create thousands of good angels who stand on his ‘left side’, as even such Torah has the power to create malachim that defend a person from harm. But if one learns Torah and does mitzvos l’shma, he will have tens of thousands of angels stationed on his ‘right side’, as he will have even protection from harm. From doing just one mitzvah l’shma, one creates legions of tens of thousands of angels to defend him!