“The trial of your faith will increase, develop, deepen, and strengthen it. “Oh,” you have said, “I wish I had more faith.” Your prayer will be heard through your having more trial. Often in our prayers we have sought for a stronger faith to look within the veil. The way to stronger faith usually lies along the rough pathway of sorrow. Only as faith is contested will faith be confirmed. Ido not know whether my experience is that of all God’s people; but I am afraid that all the grace that I have got out of my comfortable and easy times and happy hours, might almost lie on a penny. But the good that I have received from my sorrows, and pains, and griefs, is altogether incalculable. What do I not owe to the hammer and the anvil, the fire and the file? What do I not owe to the crucible and the furnace, the bellows that have blown up the coals, and the hand which has thrust me into the heat? Affliction is the best bit of furniture in my house. It is the best book in a minister’s library. We may wisely rejoice in tribulation, because it worketh patience, and patience experience, and experience hope; and by that way we are exceedingly enriched, and our faith grows strong.” 

(Spurgeon, Charles. The Trial of Your Faith, Metropolitan Tabernacle Sermons, vol. 34, 657.)