The grudges and hatred we carry are a major source of our misery which we develop when others harm us through their words and deeds or when others don't acknowledge our help or favours. The root cause of hatred is our assumption that we as well as others are 𝙠𝙖𝙧𝙩𝙝𝙖 (doer) which leads to 𝘼𝙝𝙖𝙣𝙠𝙖𝙖𝙧 (𝙖𝙝𝙖𝙢-𝙠𝙖𝙧𝙩𝙝𝙖 or I am doer) whereas our 𝙜𝙪𝙣𝙖𝙨 (characters) are in fact, the real 𝙠𝙖𝙧𝙩𝙝𝙖. This leads to 𝙠𝙖𝙧𝙢𝙖-𝙗𝙖𝙣𝙙𝙝𝙖𝙣 (bondage of action) of grudges and hatred as we are bound to 'others' for life. To overcome this, Krishna earlier advised us to drop 𝙙𝙬𝙚𝙨𝙝 (hatred) while performing 𝙠𝙖𝙧𝙢𝙖𝙨 at hand (5.3).
Krishna further says, "Whatever you do, whatever you eat do them as an offering to Me" (9.27). Earlier Krishna said that (2.14) one should be aware about the polarities of pain and pleasure generated during the interaction of senses and sense objects; and learn to ignore them as they are transient (𝙎𝙖𝙣𝙠𝙝𝙮𝙖 𝙔𝙤𝙜𝙖). Using eating as an example, He now says to offer that interaction to HIM (𝘽𝙝𝙖𝙠𝙩𝙞 𝙔𝙤𝙜𝙖). Both of these paths are to transcend polarities to be 𝘿𝙬𝙖𝙣𝙙𝙬𝙖-𝙖𝙩𝙚𝙚𝙩𝙝 (beyond polarities).
Secondly, Krishna says whatever we do, do it as an offering to HIM. This is nothing but offering our sense of doer-ship to HIM while performing the 𝙠𝙖𝙧𝙢𝙖𝙨 and in other words offering 𝘼𝙝𝙖𝙣𝙠𝙖𝙖𝙧 to HIM. Krishna assures that when we implement them we will be free of 𝙆𝙖𝙧𝙢𝙖 𝙗𝙖𝙣𝙙𝙝𝙖𝙣 (9.28) where nothing in this world can affect us as one attains ultimate freedom (𝙢𝙤𝙠𝙨𝙝𝙖).
Measuring our progress in the spiritual journey of joy is a difficult job as either our or others' outward behaviour is no indicator. The degree of 𝙆𝙖𝙧𝙢𝙖 𝙗𝙖𝙣𝙙𝙝𝙖𝙣 in terms of grudges and hatred generated in us by the events of the external world is a great indicator of our progress.