Our heavenly father tells us, that If we sow his word, it'll not return unto him void. If we sow the seed, he'll give the increase, and I think we often lose sight of the fact that the one who sows, may not necessarily do the reaping. Sometimes the seed has been sown months or years before, and then it suddenly springs to life and grows on to maturity. God works out his own plans according to his purpose, and it's our job to be in the center of his will and make sure that we faithfully sow the seeds of his word.