The Bible’s answer
Many view the cross as the most common symbol of Christianity. However, the Bible does not describe the instrument of Jesus’ death, so no one can know its shape with absolute certainty. Still, the Bible provides evidence that Jesus died, not on a cross, but on an upright stake.
The Bible generally uses the Greek word stau·rosʹ when referring to the instrument of Jesus’ execution. (Matthew 27:40; John 19:17) Although translations often render this word “cross,” many scholars agree that its basic meaning is actually “upright stake.” * According to A Critical Lexicon and Concordance to the English and Greek New Testament, stau·rosʹ “never means two pieces of wood joining each other at any angle.”
The Bible also uses the Greek word xyʹlon as a synonym for stau·rosʹ. (Acts 5:30; 1 Peter 2:24) This word means “wood,” “timber,” “stake,” or “tree.” * The Companion Bible thus concludes: “There is nothing in the Greek of the N[ew] T[estament] even to imply two pieces of timber.”
Is using the cross in worship acceptable to God?
Regardless of the shape of the instrument on which Jesus died, the following facts and Bible verses indicate that we should not use the cross in worship.
God rejects worship that uses images or symbols, including the cross. God commanded the Israelites not to use “the form of any symbol” in their worship, and Christians are likewise told to “flee from idolatry.”—Deuteronomy 4:15-19; 1 Corinthians 10:14.
Use of the cross in worship has a pagan origin. * Hundreds of years after the death of Jesus, when the churches had deviated from his teachings, new church members “were permitted largely to retain their pagan signs and symbols,” including the cross. (The Expanded Vine’s Expository Dictionary of New Testament Words) However, the Bible does not condone adopting pagan symbols to help make new converts.—2 Corinthians 6:17.
^ par. 4 See New Bible Dictionary, Third Edition, edited by D. R. W. Wood, page 245; Theological Dictionary of the New Testament, Volume VII, page 572; The International Standard Bible Encyclopedia, Revised Edition, Volume 1, page 825; and The Imperial Bible-Dictionary, Volume II, page 84.
^ par. 5 See The Expanded Vine’s Expository Dictionary of New Testament Words, page 1165; A Greek-English Lexicon, by Liddell and Scott, Ninth Edition, pages 1191-1192; and Theological Dictionary of the New Testament, Volume V, page 37.
^ par. 9 See Encyclopædia Britannica, 2003, entry “Cross”; The Cross—Its History and Symbolism, page 40; and The Companion Bible, Oxford University Press, appendix 162, page 186.
^ par. 10 See The Encyclopedia of Religion, Volume 4, page 165; The Encyclopedia Americana, Volume 8, page 246; and Symbols Around Us, pages 205-207.