In Hebrews 5 today:
Chapter 2 said we must listen very carefully to the truth we are being taught because of the danger we may drift away from that truth. Chapter 5 gives us a second reason: Believers who don’t listen won’t understand — and won’t carry their weight in the Kingdom (5:11-14). After a certain period of time, every Christian ought to be teaching others and doing justice. Christians who won’t listen, however, are “developmentally delayed” (there is a stronger word for it). They refuse to pick up knife and fork and feed themselves. Instead they sit and whine for milk — and never think what they are getting is good enough (“I’m just not being fed!”). They live like the world because they never learned to recognize the difference between right and wrong. They don’t do God’s justice because they have no idea what it looks like when his kingdom comes “on earth as it is in heaven.”
There are reasons babies are weaned from breastfeeding after a few months — not the least of which is that Daddy isn’t going to tolerate it much longer. Neither will the Lord be patient with an aging believer who refuses to grow up. If that isn’t obvious to you, skip ahead and read chapter 6, verses 7-8.