An offense committed against the sadhus who have become one with Lord Krishna and who look at all with an even eye, certainly recoils soon on the offender.
Source: Vaishnava Samhita
Some diabolical Kaapalikas were desrirous of slaying the acharya and hence they approached him to make him offer his body to Shri Rudra.
The Kaapalikas said:
Is it not true that you have no attachment to this perishable body? For, you know well that the Aatma (the soul) is immortal and the physical body is mortal.
Hence, Oh! Shankar! Please make this body an offering to Shri Rudra. We long to obtain magical powers by making a human sacrifice to Shri Rudra.
Shri Shankara replied:
Let it be so. When I knowing the Aatma, become oblivious of this physical body which is the home to all sorrows and get deeply rooted in the samadhi state then you can make an offering of my body to Lord Shiva.
What joy is there for me in this physical body? In reality I am existing as the Supreme Soul that is Immortal and All-Pervading.
Shri Sadguru Continued:
Having spoken thus, the Jagadguru (the universal preceptor) concentrated on the Truth, `I am the Supreme Soul'. Deeply immersed in meditation he reached the samadhi state and then the turiya state and became oblivious of the three worlds and totally unconscious of his physical existence.
At that time the wicked Kaapalikas approached Shri Shankara with their lips quivering in anger and with all excitement, holding the sword to kill him.
The very moment Bhagavan Shri Narasimha (Lord Vishnu in the human form with the head of a lion), the slayer of the wicked and the Protector of His devotees entered into the body of Shri Padmapada.
He had once tore to pieces the demon Hiranyakashipu impelled by His love for Prahlada. He killed the wicked now too, just as Garuda tears a snake into pieces.
Astunded all the disciples ran towards Shri Shankara. Shankara regained consciousness and prayed to Lord Purushottama.
Thus, an offense committed against the sadhus who have become one with Lord Krishna and who look at all with an even eye, certainly recoils soon on the offender.