Does God really punishes or take revenge from humans? For eg- If someone asked something from God and took a vow that if he gets that thing, he will do something. He gets that thing but he did not fulfil his vow to God. Now..will God punish really him or take revenge to him?
Does God really punish?
Yes he does, according to the Vedas. Brahman is the giver of the fruits of action, meaning he rewards and punishes accordingly.
The Brahma Sutras are a summary of the Upanishads (part of Vedas), and here is what Ramanujacharya says in his commentary on the Brahma Sutras:
Sruti and Smriti alike declare that the connexion of the individual souls with bodies of different kinds--divine, human, animal, and so on--depends on the karman of those souls; compare 'He who performs good works becomes good, he who performs bad works becomes bad. He becomes pure by pure deeds, bad by bad deeds' (Bri. Up. IV, 4, 5). In the same way the reverend Parâsara declares that what causes the difference in nature and status between gods, men, and so on, is the power of the former deeds of the souls about to enter into a new creation--'He (the Lord) is the operative cause only in the creation of new beings; the material cause is constituted by the potentialities of the beings to be created. The being to be embodied requires nothing but an operative cause; it is its own potentiality which leads its being into that condition of being (which it is to occupy in the new creation).' Potentiality here means karman.
So, the Jivas do good and bad actions and Brahman (God) punishes them accordingly.
He gets that thing but he did not fulfil his vow to God. Now..will God punish really him or take revenge to him?
If you make a vow, but then fail to fulfill it, or break the vow, then it's a sin and the person is liable to punishment.
According to Hindu Texts, It is not the God that punishes but our own mind. The mind has its own memory which is divided into three stages, conscious, subconscious, and superconscious. Subconscious does remember everything and attracts similar thoughts to do so. Accordingly, we will act to get punishment or reward.
Source: Garuda Purana