The instrument of Jesus' crucifixion (known in Latin as crux, in Greek as stauros) is generally taken to have been composed of an upright wooden beam to which was added a transom, thus forming a "cruciform" or T-shaped structure.
Most Christian denominations present the Christian cross in this form, and the tradition of the T-shape can be traced to early Christianity and the Church fathers. However, some scholars of the late 19th century have maintained that it was in reality a simple stake (crux simplex). Various authorities have then linked the cross with nature worship and pagan sex rites. This view was adopted by the Jehovah's Witnesses.
The Koine Greek terms used in the New Testament of the structure on which Jesus died are stauros (σταυρός) and xylon (ξύλον). Those words, which can refer to many different things, do not indicate the precise shape of the structure. Scholars have long known that the Greek word stauros and the Latin word crux did not uniquely mean a cross. They have known too that the words had that meaning also, and so have not considered necessarily incorrect the traditional picture of a cross with transom.
The ambiguity of the terms was noted by Justus Lipsius in his De Cruce (1594),Jacob Gretser in his De Cruce Christi (1598) and Thomas Godwyn in his Moses and Aaron (1662).
John Pearson, Bishop of Chester (c. 1660) wrote in his commentary on the Apostles' Creed that the Greek word stauros originally signified "a straight standing Stake, Pale, or Palisador", but that, "when other transverse or prominent parts were added in a perfect Cross, it retained still the Original Name", and he declared: "The Form then of the Cross on which our Saviour suffered was not a simple, but a compounded, Figure, according to the Custom of the Romans, by whose Procurator he was condemned to die. In which there was not only a straight and erected piece of Wood fixed in the Earth, but also a transverse Beam fastned unto that towards the top thereof".