Martyn Lloyd-Jones
God has chosen to call out His people by means of evangelism and the preaching of the Word. he ordains the means as well as the end.

I planted, Apollos watered, but God gave the growth. So neither he who plants nor he who waters is anything, but only God who gives the growth. He who plants and he who waters are one, and each will receive his wages according to his labor.
1 Corinthians 3:6-8