Yama and Niyama  

For any higher spiritual growth our life and its activities must be based on sound moral and ethical principles obeying strictly the universal laws of cause and effect. The great Rishi Patanjali has summarized these principles under two stages. The first is called ‘Yama' which consists of basic values that brings about a purification of our external nature, behavior patterns, attitude and activities, leading to state of stable inner peace and free us from getting unnecessarily disturbed by people or environment outside of us. The second stage is called ‘Niyama' that involves purification of our inner nature so as to maintain a still higher degree of peace and stability. It is alter we have achieved a certain degree of this inner peace and harmony within us that we can then proceed on the hard and strenuous path of converting our human nature into divine nature. 

Understood in the full sense of the meaning, the observances of yam are rules that embrace the whole of moral conduct by whose observance the yogi avoids the fundamental difficulties that blocks his progress towards self-realization. These observances develop the power of mental resistance, to oppose the desires, to indulge in activities against the spiritual law and help to neutralize the karmic effects of past mistakes. These are the foundation on which the yogi builds his spiritual life. They bring the activities of the body and mind in tune with the cosmic laws of nature producing an inner and outer well-being happiness and strength that attract the aspiring yogi to deeper spiritual practices and make him receptive to the of his Guru. 

Each of these stages has five broad principles, as outlined by Maharishi Patanjali. These principles are not the be all and end all of all spirituality. Other masters have added a few more. 

Yama  
Yama consists of Ahimsa (Non-violence), Satya (Truthfulness), Asteya (Non-stealing), Brahmacharya (Continence) and Aparigraha (Non-possessiveness). 

Ahimsa (Non-violence) 
It involves a training of the mind in non-violence or non-injury to any living being in thought, word or deed. All violence is a product of fear, weakness, ignorance, tension or anxiety. Fear and weakness go when right understanding dawns. Ahimsa is practiced based on the universal truth that all life is a connected whole. Any injury done to others will therefore necessarily come back to us in some form sooner or later as our life is intimately connected with every thing else. In the life of a yogi this is therefore one of the highest virtues to be practiced and mastered. 
In close human relationships violence consist of: 

• Harsh, abusive words and / or physical manhandling.

• Angry emotional outbursts, quick emotional judgments.

• Sarcasm, insulting speech, talking or even then thinking ill of others, or overtly critical.

• Strong expectations, skilful manipulations.