Someone beat me to it. The third temple is the church. Here are some verses.
John 2:19-21 Jesus answered and said unto them, Destroy this temple, and in three days I will raise it up. Then said the Jews, Forty and six years was this temple in building, and wilt thou rear it up in three days? But he spake of the temple of his body.
Mark 14:58 We heard him say, I will destroy this temple that is made with hands, and within three days I will build another made without hands.
1 Corinthians 3:17 If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are.
1 Corinthians 6:19-20 What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's.
Ephesians 2:19-22 Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God; And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone; In whom all the building fitly framed together groweth unto an holy temple in the Lord: In whom ye also are builded together for an habitation of God through the Spirit.
Bible prophecy is a deep subject that would requires dozens of hours to explain in detail. If you're just getting started,
Panorama of Prophecy is a good start. If you want something deep, check out
Salvation in Symbols and Signs.