duḥkhasya ca sukhasya ca

sukhaya-for happiness; duhkha-moksaya-for release from the unhappy state; kurvate-perform; dam-pati-the wife and husband; kriyah-activities; tatah-from that; anivrttih-no cessation; apraptih-no achievement; duhkhasya-of distress; ca-also; sukhasya-of happiness; ca-also.