For serving H'shem with loyalty, he will receive reward from the Creator, My He be exalted. pg 393

 One who is pure towards GD is identified and the man loyal in his service is recognized through his forbearance at a time when the wicked rule over him and humiliate him. 

 Sometimes GD bestows favor on a wicked man in order to try those who are deceptive and inwardly evil, who when they observe the prosperity of the wicked hurry to turn away from the service of GD and hasten to win the favor of the wicked and to learn from their actions. pg 393

Sometimes H'shem bestows on a wicked man favor on account of the past piety of his father in return for which it was proper to bestow benefits on the son  pg 391/393

 It may be that the Creator, May He be exalted, patiently bears with the wicked man until he repents and becomes worthy of his good fortune, as was the case with Menashe. pg 391

 A wicked man's wealth may also prove to be the primary cause of his death or undoing pg 391

 Sometimes wealth is placed in the charge of the wicked like a deposit until GD may He be exalted give him a righteous son who is worthy of it 391 

 Sometimes the opportunity to obtain his livelihood without trouble and trial might be withheld from a righteous man... because of his failure to demonstrate zeal for GD's causes and exact punishment from his contemporaries.  As to GD's favor bestowed on a wicked man, this sometimes happens on account of a previous good deed for which GD rewards him in this world ( so that he does not have to pay him later in the World to Come) 391