Frank J. Wilstach, comp. A Dictionary of Similes. 1916.

Tedious

Tedious a task for the mind as oakum-picking or stone-breaking can be for the body.
—Arthur Acheson

Tedious as a twice-told tale.
—Homer

Tedious and dull as truth.
—Henry Mackenzie

Tedious as dull sorrows.
—Philip Massinger

Tedious as a king.
—William Shakespeare

Tedious
As a tired horse, a railing wife.
—William Shakespeare

So tedious is this day,
As is the night before some festival
To an impatient child, that hath new robes,
And may not wear them.
—William Shakespeare

As tedious as a guilty conscience.
—Cyril Tourneur