People can feel so confident in their own abilities that they feel no need of HKB"H...
Words do not suffice to explain the great purpose served by recognizing G-d's greatness and sovereignty, and man's lowliness before Him. No traits are more disgraceful than haughtiness and egotism. They are the root of evil and ugliness.The only thing we can be absolutely sure of in this world is that Hashem holds all the power.
...Once a person ascribes importance to himself, he will worship himself, seek pleasure for himself and let all his selfish traits burst forth, for example, lust, anger and cruelty. This because all of the these traits feed the demands of the arrogant person who seeks honor and wealth so as to adorn himself and satisfy his arrogance.
...Haughtiness leads directly to heresy, and it is wealth and materialism, more than anything else, which give life to haughtiness and lust: "They shall have eaten their fill and waxed fat and turned unto other gods and served them and despised Me (Deut. 31:20); and "Jeshurun waxed fat and rebelled (Deut. 32:15).
...The Torah came into the world only to eradicate haughtiness from the world, and happy is he who succeeds in suppressing his evil impulse, since for this he was created.
...the more a person gives of himself and of his own possessions, the more he diminishes himself and suppresses his own evil impulse, which is man's purpose.
...One who concedes to his fellow man, who transcends his own nature and shows consideration to others, will succeed in diminishing his own arrogance and lust, and that is man's purpose. For this reason, the entire Torah is a commentary on this, and a Jew is obligated to fulfill all the commandments and to believe all of G-d's tenets, undertaking the yoke of Heaven.
...We have seen that man's purpose in the world is to come to know G-d's awesome, astonishing, remarkable greatness and to bow to Him as Supreme King. Simultaneously we must recognize our own lowliness, vanquish our pride, accept upon ourselves the yoke of His kingdom and cling to His commandments and attributes.
[Or Hara'ayon, Chapter Three: "Humility, Submission and Lowliness," pp. 46-49, 70]