He makes me lie down in green pastures,We see two things here, lying down and being led, we see food and drink.
he leads me beside quiet waters,
These things speak of resting, of peace, of nourishment, of guidance. When we are in Christ we have all that we need. I would say though that we need to consider all that we need, for truly all that we need is Christ Himself. (consider John 6:25-59)
Some people come to Jesus as if he is some genie in a bottle. Just when you need something, you pray a passage like psalm 23 and as long as you have enough faith, He will give you what you want. There are some who continue this way, when all along Christ is attempting to change those wants. HE is attempting to transform you.
If you seek Him today, the Good Shepherd will lead you beside the waters and show you where to rest.