New World Translation, Matthew 27:
There are clues that point to the latter. Thomas was skeptical in John 20:
A chapter later, Jesus prophesied the manner of Peter's death in John 21:
It is a ligature composed of a superposition of the Greek letters tau (Τ) and rho (Ρ). Some 2nd-century manuscripts used the staurogram to spell G4716.
There are also artifacts from the Shroud of Turin:
Lexically, σταυρός is ambiguous. However, there are some strong textual and physical evidences that point to the T-shaped cross.
Thayer's Greek Lexicon:40 and saying: “You who would throw down the temple and build it in three days,+ save yourself! If you are a son of God, come down off the torture stake [G4716 σταυρός]!”
- an upright stake, especially a pointed one (Homer, Herodotus, Thucydides, Xenophon).
- a cross.
Was Jesus nailed on an I-shaped stake or a T-shaped cross?and saying, “You who are going to destroy the temple and build it in three days, save yourself! Come down from the cross, if you are the Son of God!”
There are clues that point to the latter. Thomas was skeptical in John 20:
The T-shape cross required more than one nail.25 Unless I see in His hands the imprint of the nails, and put my finger into the place of the nails, and put my hand into His side, I will not believe.”
A chapter later, Jesus prophesied the manner of Peter's death in John 21:
on the horizontal beam of the cross18 Truly, truly, I say to you, when you were young, you used to dress yourself and walk wherever you wanted, but when you are old, you will stretch out your hands,
This is the staurogram:and another will dress you and carry you where you do not want to go.” 19 (This he said to show by what kind of death he was to glorify God.) And after saying this he said to him, “Follow me.”

It is a ligature composed of a superposition of the Greek letters tau (Τ) and rho (Ρ). Some 2nd-century manuscripts used the staurogram to spell G4716.
There are also artifacts from the Shroud of Turin:
Was Jesus nailed on an I-shaped stake or a T-shaped cross?There is evidence that the body once folded in the Shroud was the victim of a Roman crucifixion. Though used as a method of execution by the Persians, the Phoenicians, the Greeks, and other societies of antiquity, crucifixion in the Roman world was distinctive in a number of ways. Flogging invariably preceded execution and was usually carried out as the condemned proceeded to the crucifixion site; the victim was made to carry his own crossbar and was tied or nailed thereto and then hoisted onto a cross; or a T-shaped frame. Evidence in the Shroud image attests to each of these traits
Lexically, σταυρός is ambiguous. However, there are some strong textual and physical evidences that point to the T-shaped cross.