The utterance of God is a lamp, whose light is these words: Ye are the fruits of one tree, and the leaves of one branch. Deal ye one with another with the utmost love and harmony, with friendliness and fellowship.
…Consort with all men, O people of Bahá, in a spirit of friendliness and fellowship. If ye be aware of a certain truth, if ye possess a jewel, of which others are deprived, share it with them in a language of utmost kindliness and good-will. If it be accepted, if it fulfil its purpose, your object is attained. If any one should refuse it, leave him unto himself, and beseech God to guide him. Beware lest ye deal unkindly with him. A kindly tongue is the lodestone of the hearts of men. It is the bread of the spirit, it clotheth the words with meaning, it is the fountain of the light of wisdom and understanding…”
Gleanings From the Writings of Bahá’u’lláh, pages 288 & 289
“We must not consider any people the people of Satan, but know and recognize all as the servants of the one God. At most it is this: Some do not know; they must be guided and trained. They must be taught
to love their fellow creatures and be encouraged in the acquisition of virtues. Some are ignorant; they must be informed. Some are as children, undeveloped; they must be helped to reach maturity. Some are ailing, their moral condition is unhealthy; they must be treated until their morals are purified. But the sick man is not to be hated because he is sick, the child must not be shunned because he is a child, the ignorant one is not to be despised because he lacks knowledge. They must all be treated, educated, trained and assisted in love. Everything must be done in order that humanity may live under the shadow of God in the utmost security, enjoying happiness in its highest degree.”
The Promulgation of Universal Peace, p. 269