Question

If a brahmin has qualities of sudra should he be prohibited from duties of a brahmin?

Answer

A Brahmin who does not have the qualities of an ideal Brahmin should have to be treated accordingly.There are many verses in Smritis which say so.

Manu Smriti 4.245. A Brahmana who always connects himself with the most excellent (ones), and shuns all inferior ones, (himself) becomes most distinguished; by an opposite conduct he becomes a Sudra.

Manu smriti 8.102. Brahmanas who tend cattle, who trade, who are mechanics, actors (or singers), menial servants or usurers, the (judge) shall treat like Sudras

The panegyrics, the flatterers, cheats, those who act harshly, and those who are avaricious, these five Brahmanas should never be adored, even if they are equal to Vrihaspati in learning.(Atri Smriti Chapter 1,Verse 273)

Similarly a Brahmin who does not know the Gayatri or who fails do his religious duties is also a Sudra by karmas.

  1. A Brahman, ignorant of the Gayatri hymn, is more unclean than even a Sudra ; the Brahmans who know the nature and the sanctity of the Gayatri hymn, are honored and revered by all persons.(Parashara Smriti,Chapter 8,Verse 24)

And a Brahmin who is of unrighteous conduct is a Chandala.

He who sets his face against righteousness, is but a Chandala by his acts. He gains nothing by being a mendicant, or by worshipping the household fire.(Parashara Smriti,Chapter 8 )

But, i have not found any verses like the ones you are looking for.Which say that a bad Brahmin should be prohibited from participating in religious acts.On the contrary i found this:

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25.Even a Brahman of a bad character deserves respect; but not so a Sudra, even though his passions may have been subdued by him. Who would quit a wicked cow, and try to milk a docile female ass?(Parashara Smriti,Chapter 8,Verse 25)

This is possibly because the Smritis give considerable importance to the sanctity of a Brahmin birth and also to the power of the purificatory Samskaras.

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