Hi Guillermo,
Most likely you want this Sutta:
MN 24, PTS: M i 145
Ratha-vinita Sutta: Relay Chariots
http://www.accesstoinsight.org/tipitaka/mn/mn.024.than.html
Ven. Thanissaro's footonote [2].
Ven. Sariputta and Ven. Punna speak of this list of seven purities — purity in terms of virtue, mind, view, the overcoming of perplexity, knowledge & vision of what is & is not the path, knowledge & vision of the way, and knowledge & vision — as if it were a teaching familiar to both of them, and yet nowhere else is it mentioned as a Buddhist teaching in the discourses. The Atthaka Vagga (Sn 4), however, mentions various non-Buddhist sectarians who spoke of purity as the goal of their teaching and who variously defined that purity in terms of virtue, view, knowledge, & practice. Perhaps the seven types of purity listed in this discourse were originally non-Buddhist teachings that were adopted by the early Buddhist community and adapted to their own purpose for showing that these seven forms of purity functioned not as a goal of practice but as stages along the path to that goal. At any rate, this list of the seven purities formed the framework for Buddhaghosa's Visuddhimagga (The Path of Purity), the cornerstone of his Pali commentaries, in which the seven purities cover all three parts of the threefold training in virtue, concentration, & discernment.
However, you won't get much detail from the Sutta. Here's the entire map:
"In the same way, my friend, purity in terms of virtue is simply for the sake of purity in terms of mind. Purity in terms of mind is simply for the sake of purity in terms of view. Purity in terms of view is simply for the sake of purity in terms of the overcoming of perplexity. Purity in terms of the overcoming of perplexity is simply for the sake of purity in terms of knowledge & vision of what is & is not the path. Purity in terms of knowledge & vision of what is & is not the path is simply for the sake of purity in terms of knowledge & vision of the way. Purity in terms of knowledge & vision of the way is simply for the sake of purity in terms of knowledge & vision. Purity in terms of knowledge & vision is simply for the sake of total Unbinding through lack of clinging. And it's for the sake of total Unbinding through lack of clinging that the holy life is lived under the Blessed One."
MIke