Herbert on worrying about the future

Some lines from "The Discharge"

Only the present is thy part and fee.
And happy thou,
If, though thou didst not beat thy future brow,
Thou couldst well see
What present things requir'd of thee


They ask enough; why shouldst thou further go?
Raise not the mud
Of future depths, but drink the clear and good.
Dig not for woe
In times to come; for it will grow.

...

Things present shrink and die: but they that spend
Their thoughts and sense
On future grief, do not remove it thence
But it extend,
And draw the bottom out to an end.

God chains the dog til night: wilt loose the chain,
And wake thy sorrow?
Wilt thou forestall it, and now grieve to morrow,
And then again
Grieve over freshly all thy pain?

Either grief will not come:or if it must
Do not forecast.
And while it cometh, it is almost past.
Away distrust:
My God hath promised, He is just.