Envy

When, however, he realized that his deed had been exposed, he seized the pen of calumny and wrote unto the servants of God, attributing what he had himself committed unto Mine own peerless and wronged Beauty. His purpose was none other than to inspire mischief amongst God's servants, and to instil hatred into the hearts of those who had believed in God, the All-Glorious, the All-Loving . . . Nor did he find respite from what he harboured in his bosom until he had committed that which no pen dare describe, and by which he disgraced the dignity of My station and profaned the sanctity of God, the Almighty, the All-Glorious, the All-Praised. Were God to turn all the oceans of the earth into ink and all created things into pens, they would not suffice Me to exhaust the record of his wrongdoings. Thus do We recount that which befell Us, that haply ye may be of them that understand.

Bahá’u’lláh, The Summons of the Lord of Hosts, p. 16

Highly jealous of the rising prestige of Bahá’u’lláh and aware of the declaration of His station as 'He Whom God shall make manifest', Mírzá Yahyá decided it was time to come into the open and wrest the leadership of the community from the hands of the One who had been his guide and refuge all his life, and who had, through His sin-covering eye, concealed many of his shameful deeds. Emboldened by Bahá’u’lláh's loving forgiveness, duped by Siyyid Muhammad's enticing prospects and spurred on by his own ambitious lust for leadership, Mirza Yahya embarked upon a path which is exclusively reserved for the evil, namely, to attempt a person's life. This was his only way, for he knew that he had no power whatsoever to confront Bahá’u’lláh.

Adib Taherzadeh, The Revelation of Bahá’u’lláh v 2, p. 152-153

Judas Iscariot was the greatest of the disciples, and he summoned the people to Christ. Then it seemed to him that Jesus was showing increasing regard to the Apostle Peter, and when Jesus said, 'Thou art Peter, and upon this rock I will build My church,' these words addressed to Peter, and this singling out of Peter for special honour, had a marked effect on the Apostle, and kindled envy within the heart of Judas. For this reason he who had once drawn nigh did turn aside, and he who had believed in the Faith denied it, and his love changed to hate, until he became a cause of the crucifixion of that glorious Lord, that manifest Splendour. Such is the outcome of envy, the chief reason why men turn aside from the Straight Path. So hath it occurred, and will occur, in this great Cause. But it doth not matter, for it engendereth loyalty in the rest, and maketh souls to arise who waver not, who are fixed and unshakeable as the mountains in their love for the Manifest Light.

‘Abdu’l-Bahá, Selections from the Writings of ‘Abdu’l-Bahá, p. 163