“They have no root in themselves, but endure for a while; then, when tribulation or persecution arises on account of the word, immediately they fall away.” (Mark 4:17)
The faith of some is broken instead of built by suffering. Jesus knew this and described it here in the parable of the four soils. Some people who hear the word receive it at first with gladness, but then suffering makes them fall away.
So, affliction does not always make faith stronger. Sometimes it crushes faith. And then come true the paradoxical words of Jesus, “The one who has not, even what he has will be taken” (Mark 4:25).
This is a call for us to endure suffering with firm faith in future grace, so that our faith might grow stronger and not be proved vain (1 Corinthians 15:2). “To the one who has, more will be given” (Mark 4:25). Knowing God’s design in suffering is one of the main means of growing through suffering.
If you think your suffering is pointless, or that God is not in control, or that he is whimsical or cruel, then your suffering will drive you from God, instead of driving you from everything but God — as it should. So, it is crucial that faith in God’s grace includes the faith that he gives grace through suffering.