A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
psa 36:1On servant of the Lord, see on Psa 18:1, title. The wickedness of man contrasted with the excellency of God's perfections and dispensations; and the benefit of the latter sought, and the evils of the former deprecated. (Psa 36:1-12)
The general sense of this difficult verse is, "that the wicked have no fear of God." The first clause may be rendered, "Saith transgression in my heart, in respect to the wicked, there is no fear," &c., that is, such is my reflection on men's transgressions.
psa 36:2This reflection detailed.
until his iniquity--literally, "for finding his iniquity for hating"; that is, he persuades himself God will not so find it--"for hating" involving the idea of punishing. Hence his words of iniquity and deceit, and his bold rejection of all right principles of conduct. The climax is that he deliberately adopts and patronizes evil. The negative forms affirm more emphatically their contraries.
psa 36:5mercy . . . and . . . faithfulness--as mercy and truth (Psa 25:10).
psa 36:6righteousness [and] judgments--qualities of a good government (Psa 5:8; Psa 31:1). These all are set forth, by the figures used, as unbounded.
psa 36:7shadow of thy wings--(Compare Deu 32:11; Psa 91:1).
thy house--residence--for the privileges and blessings of communion with God (Psa 23:6; Psa 27:4).
river of thy pleasures--plenteous supply; may allude to Eden.
psa 36:9Light is an emblem of all blessings, given of God as a means to gain more.
psa 36:10that know thee--right knowledge of God is the source of right affections and conduct.
psa 36:11foot of . . . hand . . . wicked--all kinds of violent dealing.
psa 36:12There--in the acting of violence, they are overthrown. A signal defeat.