Sutra:
167. avan upAyamAmidaththil thAn purushakAramAyirukkum; avan prApyanAmidaththil thAn prApyaiyumAy kainkarya varththikaiyumAyirukkum.

Meaning:
When He is the upAya (tha is, the one giving moksha), She will not be concerned with being the means and will be focused on being the mediator. When He becomes the upEya and accepts service, She too will become one who accepts the service, as well as one who increases the service provided by the chetana manifold.

Sri PBA Swami's Sarartha Deepikai:
In both parts of the mantra, Sri is expressed as being eternally with Him; but Her state should be considered according to the condition surrounding each.

When He takes on the role of upAya and removes that which is not wanted and gives that which is desired to the chetana, She will take on the role of mediator. When He takes on the role of upEya and receives the service from the chetana, She too becomes the upEya and will receive the service. Also, She will increase the service rendered by the chetana manifold and will make His divine heart pleased.

Therefore, the eternal togetherness spoken in the first part of the mantra is directed at the mediatrix role of Sri and the same in the second part of the mantra speaks of Her receiving service and boosting the chetana's service to please His divine heart.