Emblematic statements are sets of comparisons: A is to B as C is to D.
As the deer pants for the water brooks,
So pants my soul for You, O God.
A deer needs water, as does all of God’s creatures. In the same way each person needs God to be healthy, well, and satisfied.
As a ring of gold in a swine's snout,
So is a lovely woman who lacks discretion.
Rings in a pig’s snout are used to lead the animal, especially when it is being stubborn. Making a pig’s nose ring of gold doesn’t make the pig any better or finer. In the same way beauty doesn’t make a woman better or finer when she lacks good judgment.