It is the Glory of the Lord to conceal a thing, and the honor of kings to search out a matter. Pro.25:2
Throughout scripture God has given us visible ways to teach us spiritual reality, this is just a sample of the revelation that unfolds as we come to understand these truths.
Everything God has ever said, speaks to us of Jesus Christ His church and His Kingdom.
A type is a fore-shadowing of a future fulfillment demanding an anti-type.
A symbol is material emblem portraying an unfolding a spiritual reality.
A few examples of types are the tabernacles,the temples, the feast, the offerings, the nations, and the old testament nation of Israel.
Once you have the anti-type you never again go back to the type He takes away the first to establish the second. Heb.10:9b
Examples of symbols are wine, rain, bread, oil, fire, wind, milk,meat,water,hail,river and many many more, all of them to let us know what the Holy Spirit is like and what he is doing.