Does taking non-vegetarian food prevent us from becoming spiritual and getting salvation?
I have found some scriptures of what they say about eating non-vegetarian from a vlog:
Anumantaa vishasitaa nihantaa krayavikrayee Samskartaa chopahartaa cha khadakashcheti ghaatakaah : Manusmrithi 5.51
Those who permit slaying of animals, those who bring animals for slaughter, those who slaughter, those who sell meat, those who purchase meat, those who prepare dish out of it, those who serve that meat and those who eat are all murderers.
Breehimattam yavamattamatho maashamatho tilam Esha vaam bhaago nihito ratnadheyaaya dantau maa hinsishtam pitaram maataram cha : Atharvaveda 6.140.2
O teeth! You eat rice, you eat barley, you gram and you eat sesame. These cereals are specifically meant for you. Do not kill those who are capable of being fathers and mothers.
Aghnyaa yajamaanasya pashoonpahi : Yajurveda 1.1
“O human! animals are 'Aghnya' – not to be killed. Protect the animals”
"He who desires to augment his own flesh by eating the flesh of other creatures, lives in misery in whatever species he may take his [next] birth." (Mahabharata, Anu.115.47)
So there's no specific texts I could find where we can conclude that we cannot get Moksha, but yes our texts seem to indirectly point out that its a sin.
But yes some texts also say that one can still be a good devotee if he consumes meat. I would suggest to read KulArnava Tantram, Chapter 5, Verse 45 which specifies that Lord Shiva doesnot accept the consumption of meat unless its a part of a ritual. This one:
Pitridevatayajneshu VaidahimsA Vidhiyate | AtmArtham PrAninAm HimsA kadAchinnoditA Priye ||
In Pitru Yanjna and Deva Yajnas sacrificial killing is allowed. But other than that the Shastras never allow prani himsa (killing) for one's own pleasure.
So one can still be a devotee but as I said, our texts seem to indirectly point that its a sin(that's what I think).
It does not seem that meat eating will definitely hinder spiritual progress. Some restraint is the advice.
Chandogya Upanishad says that some spiritual aspirant takes a vow to not eat fish and meat for a year or to permanently stop eating non-veg food. The exact shloka is:
He who thus knows this Yajnayajniya Saman, woven in the limbs of the body, is endowed with all the limbs, and is not crippled in any limb; he reaches the full length of life, lives gloriously, becomes great with offspring and cattle and great also with fame. His holy vow is that he should not eat fish and meat for a year, or rather, he should not eat fish and meat at all.
Chandogya Upanishad 2.19.2
In spiritual progress it is said that one should not consume non vegetarian food and excessive oily foods and mostly rajasic and tamasic foods
One should follow sattvic diet if one is interested in spiritual saadhana(progress)
Firstly rajasic brings intense energy to fulfill needs Tamasic decreases the energy
Sattvic diet brings peace in one's mind Once the mind is at peace. Spiritual progress is easy
Now to answer your question Non vegetarian food contains an another jeev atma(soul) So consuming it will disturb your soul's progress as you are consuming another soul
So they say do not consume non vegetarian food if you want to progress spiritually
Salvation entirely depends upon the progress made in past lives. If you have desires it is better to accomplish them rather than supress them as they can erupt like a dormant volcano
I have gotten this information not directly from a source but a collection and swami sivananda books and my own experience.
You can read about this in many of his books
I hope your question is answered