Jesus taught in front of thousands of people throughout his lifetime. Wherever he went, huge crowds followed him (Mark 5:24, Mark 10:1, Matthew 4:25, Matthew 8:1, Matthew 14:13).
But not everyone that Jesus taught continued to follow him. Not everyone that followed him became his disciple. And even within his disciples, Jesus had an inner circle—the ones he invested in the most (Mark 9:2–3).