The references in the New Testament to Christ hanging on ''a tree'', at least sometimes have reference to Deuteronomy 21:22-23 (cf. Joshua 6:29), in which criminals after being executed (it is believed) were hung from a tree as a warning and testimony.
At least in later years it is clear from the Jewish Talmud that execution itself was sometimes by strangulation, but not by hanging and not from a tree.
The description of the Cross as ''a tree'' reminds one that there may be typology in the Tree of Life in Genesis, which is fulfilled by Christ turning the Tree of suffering, shame and cursing, His Cross, into a ''Tree of Life'' for His people.
By crucifying Christ and consequently leaving Christ on the Cross during a period of darkness ('' night'' Psalm 22:2), the Jews contravened Deuteronomy 21:22-23, defiled their Land, and brought themselves and their Land under the curse of God