Parashas Vayikra · Aliyah 1 · Passuk 5
Chabad.org — English translation + Rashi
Torah Temima points to Zevachim 53b (verified; saviv and the two throwings that equal four).
E-Daf.com — Tsurras Hadaf (size=3)
HebrewBooks / Shas PDF of the daf
English: “And they shall throw… all around” — if it said only “they shall throw,” I might think one throwing suffices; therefore it says “all around.” If it said only “all around,” I might think he should encircle it like a thread; therefore it says “they shall throw.” How so? He throws in the form of a gamma (covering two walls at each of two opposite corners).
Custom (resolution of two phrases in one passuk) — “throw” and “all around” together define the required blood applications for the olah.
The olah requires two throwings of blood that effectively reach all four sides of the altar (the classic “two that are four”), not a single toss and not a continuous smear around the rim.