Mark 3:6: What is an heart with envy fraught

What is an heart with envy fraught,
And pride, the Pharisaic leaven!
It poisons every word and thought.
Into the hands of Satan given.
Contrives to' advance the murderer's cause.
And nails the Saviour to His cross.

By the malicious fiend possess'd,
Evil he counts his only gain,
Virtue he turns into a pest,
The balm of Gilead into bane;
By good his wretched soul he kills,
By good his own damnation seals.