Importance of Sruti and Smrti

In the Yajnavalkya-smrti it is said:

sruti-smrti-sadacarah
svasya ca priyam atmanah
samyak sankalpajah kamo
dharma-mulam idam smrtam

One should learn human behavior from sruti, the
Vedas, and from smrti, the scriptures following
the Vedic principles. Srila Rupa Gosvami in his
Bhakti-rasamrta-sindhu says:

sruti-smrti-puranadi-
pancaratra-vidhim vina
aikantiki harer bhaktir
utpatayaiva kalpate

The purport is that to become a devotee one must
follow the principles laid down in sruti and
smrti. One must follow the codes of the puranas
and the pancaratriki-vidhi. One cannot be a pure
devotee without following the sruti and smrti,
and the sruti and smrti without devotional
service cannot lead one to the perfection
of life.