Thou wert created to bear and endure, O Patience of the worlds.

Bahá’u’lláh, The Fire Tablet, Bahá’í Prayers, p. 317

... Show the world that in spite of the utmost suffering, poverty, sickness, you have something which gives you comfort, strength and peace—that you are happy—serene—satisfied with all that is in your life.

‘Abdu’l-Bahá, Star of the West, Volume 9, p. 86

All mankind is suffering in this earthly world; there is no one in such tranquility that this (state) might have been a reward for his good deeds in a former life and there is no soul so happy that this might be the fruit of his past pain!

‘Abdu’l-Bahá, Tablets of ‘Abdu’l-Bahá v3, p. 643

'Does the soul progress more through sorrow or through the joy in this world?' ‘Abdu’l-Bahá. -- 'The mind and spirit of man advance when he is tried by suffering. The more the ground is ploughed the better the seed will grow, the better the harvest will be. Just as the plough furrows the earth deeply, purifying it of weeds and thistles, so suffering and tribulation free man from the petty affairs of this worldly life until he arrives at a state of complete detachment. His attitude in this world will be that of divine happiness. Man is, so to speak, unripe: the heat of the fire of suffering will mature him. Look back to the times past and you will find that the greatest men have suffered most.'

‘Abdu’l-Bahá, Paris Talks, p. 178

He who through suffering has attained development, should he fear happiness?' ‘Abdu’l-Bahá. -- 'Through suffering he will attain to an eternal happiness which nothing can take from him.

‘Abdu’l-Bahá, Paris Talks, p. 178

However afflictive your sufferings may be, stay ye undisturbed, and with perfect confidence in the abounding grace of God, brave ye the tempest of tribulations and fiery ordeals.

‘Abdu’l-Bahá, Selections from the Writings of ‘Abdu’l-Bahá, p. 73