Here’s Macbeth’s famous “tomorrow” soliloquy (5.5.19-28):

Tomorrow, and tomorrow, and tomorrow,
Creeps in this petty pace from day to day,
To the last syllable of recorded time;
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life’s but a walking shadow, a poor player,
That struts and frets his hour upon the stage,
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.
And here’s James 4:14:
Whereas ye know not what shall be on the morrow. For what is your life? It is even a vapour, that appeareth for a little time, and then vanisheth away.
It’s interesting, is it not, not only that the central point of each is the ephemerality of life — but that each begins with a reference to our next day, tomorrow?  A connection is made between our transitoriness and the limited control we have over what will next befall us on this mortal coil.  But, it must be added, the similarities go only so far:  James knows that Macbeth is wrong in his despairing conclusion that our lives signify nothing — at least, they are not meaningless if we have been saved.