"Your Reverence, so too, purity of morality is only for the purpose
of (establishing) purity of (concentration of) mind. Purity of
(concentration of) mind is only for the purpose of (establishing)
purity of view. Purity of view is noly for the purpose of
(establishing) purity of (knowledge in) overcoming doubt. Purity of
(knowledge in)overcoming doubt is only for the purpose of
(establishing) purity of Purity of knowledgr and insight into what
is Magga and what is not Magga. Purity f knowledge and insight into
what is Magga and what is not Magga is only for the purpose of
(establishing) purity of knowledge and insight into the couirse of
vipassanaa practice (in proper order). Purity of knowledge and
insight into the course of vipassanaa practice (in proper order) is
only for the purpose of (establishing)purity of Magga knowledge and
insight. Purity of Magga knowledge and insight is only for the
purpose of (realizing) Nibaana, uncaused, the unconditioned. Your
Reverence! It is only for the purpose of (realizing) Nibbaana, the
uncaused, the unconditioned, that I practice the Noble Life of
Purity under the Bhagavaa." [M. I. Rathaviniita Sutta].

It seems that mentioning about Seven Visuddhis and Vipassana is
already in the Tipitaka as it is in translation of Rathaviniita
Sutta clearly stated. Many around me had said that the term
Vipassana is really found in Tipitaka, but mainly could be found in
Atthaakathas etc.,(commentaries and sub-commentaries). So here it
is, found in Majjhimanikaaya, Muulapa.n.naasa Paa.li, Rathaviniita
Sutta. Where else could it be found?
with reverence
sitalo