1 Kings 6:31

And for the entering of the oracle he made doors [of] olive
tree
The door of the holy of holies was a two leaved or folding door, made of olive wood; typical of Christ, the door into the church above and below, the way to heaven and eternal life, the true olive tree:

the lintel [and] side posts [were] a fifth part [of the wall];
four cubits, twenty cubits being the breadth of the oracle; or the lintel was four cubits, twenty being the height of it also, ( 1 Kings 6:20 ) .