‘Abdu’l Bahá on tests

Tests are a means by which a soul is measured as to its fitness, and proven out by its own acts. God knows its fitness beforehand, and also his unpreparedness, but man, with an ego, would not believe himself unfit unless proof were given him. Consequently his susceptibility to evil is proven to him when he falls into the tests, and the tests are continued until the soul realizes its own unfitness, then remorse and regret tend to root out the weakness. The same test comes again in greater degree, until it is shown that a former weakness has become a strength, and the power to overcome evil has been established.

‘Abdu'l Bahá, in The Eternal Quest for God, p 131