After the decline of Bhuddhism due to the [*efforts of this*] trio [*Kumarila Bhatta, UdayanAchAryA and Shankara*], only the school of [*our*] AchAryAl got established in this land. The sanAdhana vEdic
religion, also known as smArtha sampradhAyam - whose ultimate state is the advaitic gyAna, given by upanishads and established through the elaborate discussions by AchAryAl - alone got stabilised once
However, the advaithAnubhavam is not feasible for every one. By and large, people were engaged in vEdic karmAs and Ishvara upAsanA. But they did not carry them out, like pUrva mImamsakAs, with an attitude, "karmA is every thing; Even a SvAmi is not required [*for the fruits *]". As shown by AchAryAl, they accepted the Ishvara and engaged in karmAs with the sense of dedication [*of phala *] to Him.
Whenever we do any karmA, don't we say nowadays, during the sankalpam at the begining, that it is being done for the prIthi [*pleasure*] of paramAthma (paramEshvara prIthyartham) ?
THIS SANKALPAM HAS BEEN INTRODUCED (and ordained) BY OUR ACHARYAL ONLY.
Before Him, the sankalpam was not like this. He designed the sankalpam this way to avoid such misinterpretations as,'the fruits of a karmA belongs/goes to the karthA himself and one can obtain the fruits directly from the karmA instead of being bestowed by an Ishvara'. He got all vEdic karmas - right from a simple karma to yAga and yajnAs - dedicated to IshvarA (IshvarArpanam).
When the original vEdic religion started adopting the smrithis or dharma shAstrAs, which depend on and follow the vEdAs, it came to be known as smArtha religion. They are not different. The vEdic religion itself is smArtham. The karmAs are prescribed, in vEdAs, to becarried out only with a sense of dedication to IshvarA, for obtaining 'chittha shudhhi'. Only the pUrva mImAmsakAs, who came later created the confusion. AchAryAl has just rectified that. In other words, He rejuvenated the 'original' and ancient smArtha religion and re-established the same [*again*].