Remember when the author said that Jesus was like a Jewish high priest? Well, let us explain…
High priests are kind of like a go-between for the people and God. They offer gifts and sacrifices in the temple so that anyone who's sinned can make things right with God. They also have to be gentle when they're dealing with these sinners because, hey, they're sinners themselves.
One does not simply walk into Mordor and one does not simply appoint himself to be the high priest. Jesus is no different.
The high priest doesn't get elected. He's hand-picked by God, just like Aaron was in Exodus…and just like Jesus was.
So, God appointed Jesus to be the high priest for all the people in the whole world. He never sinned himself, but he earned his stripes by becoming human, obeying God, suffering, and dying.
Now a jab at the listeners (the folks it was addressed to almost 2,000 years ago): they're a little bit dim-witted.
Yeah, they're slacking a bit in the whole understanding-God-and-the-mysteries-of-the-universe department.
The author thinks they're a bit like little babies who aren't quite ready for solid food yet.
Mature Christians, on the other hand, know the difference between good and evil and can handle solid food (i.e., complex theological discussions).