Daniel 5:1-6, 13-14, 16-17, 23-28 / Luke 21:12-19
To make a notice or an official statement, we would use the phrase "Put it in black and white".
Obviously it means to put that notice or statement in writing and to have it recorded and filed. That is how it is usually done.
To write it on the wall would be a crude way of doing it. But whether the notice is pasted on the wall or written on the wall, it would mean something important or something serious.
In the 1st reading, we heard of something that is very startling and even frightening. The fingers of a human hand appeared and began to write on the plaster of the palace wall.
Those words "Mene, Mene, Tekel and Parsin" pronounced judgement on king Belshazzar who had used the sacred vessels that were looted from the sanctuary of the Temple in Jerusalem and used it for his profane merry-making.
That act of profanity was probably the last straw of all his abuses of power that literally made God's hand write out a judgement against him.
In the gospel, as Jesus talked about the persecutions that we as His disciples will have to face, He also said: Keep this carefully in mind - you are not to prepare your defence, because I myself shall give you an eloquence and a wisdom that none of your opponents will be able to resist or contradict.
It means that in the face of persecution, we must have the faith and the endurance to see God's hand write out the directions for us.
But more importantly, we must know that we are always in His hand, our names are written in His palm, and His Word will not be written on walls but written by our lives.