Adjective : to talk for an unmerciful length of time.    From Dictionary.com. 

How can you preach against unmercifulness, while you are so unmerciful?.    From Wordnik.com.  [The Reformed Pastor] Reference

There is an element of unmercifulness in the candour of La.    From Wordnik.com.  [Three French Moralists and The Gallantry of France] Reference

Of mercifulness and unmercifulness, ch.xi. 17; xii. 10; xiv.    From Wordnik.com.  [Commentary on the Whole Bible Volume III (Job to Song of Solomon)] Reference

Eliphaz had particularly charged Job with unmercifulness to the poor.    From Wordnik.com.  [Commentary on the Whole Bible Volume III (Job to Song of Solomon)] Reference

The principles by which Job was restrained from all uncharitableness and unmercifulness.    From Wordnik.com.  [Commentary on the Whole Bible Volume III (Job to Song of Solomon)] Reference

For the first time he felt, rid of all disguise, the unmercifulness which was imminent in this or that transgression of his.    From Wordnik.com.  [Pelle the Conqueror — Volume 02] Reference

And yet you will do a thousand times more against yourselves, even cast away both soul and body for ever, and never complain of your own unmercifulness!.    From Wordnik.com.  [A Call to the Unconverted to Turn and Live] Reference

Let him testify to them; let him tell them what condition I am in, and that I brought myself to it by my luxury and sensuality, and my unmercifulness to the poor.    From Wordnik.com.  [Commentary on the Whole Bible Volume V (Matthew to John)] Reference

The difficulty was, as Henry had found at Harfleur, Rouen, and many other places, to enforce forbearance on his soldiery, who regarded plunder as their lawful prey, the enemy as their natural game, and the trouble a city had given them as a cause for unmercifulness.    From Wordnik.com.  [The Caged Lion] Reference

In times past men were full of pity and compassion, but now there is no pity; for in London their brother shall die in the streets for cold, he shall lie sick at the door between stock and stock, I cannot tell what to call it, and perish there for hunger: was there ever more unmercifulness in Nebo?.    From Wordnik.com.  [Sermons on the Card] Reference

There are sins which are very apt to insinuate themselves into the callings and circumstances of men, both of high and low degree, that do easily beset them; as, hardness, oppression, severity, and unmercifulness, in those that are great and have large possessions; and deceit, equivocations, over-reachings, in those of more ordinary employments.    From Wordnik.com.  [The Sermons of John Owen] Reference