In an effort to drive home the difference between the flesh and the Spirit Paul uses the analogy of ones body being the temple of the Holy Spirit. The flesh is preserved for the Spirit and when one tampers with it in an unholy manner then God does intervene. This analogy is pertinent historically because the Corinthians had temples woven into the fabric of their culture.
Temple of the Imperial Cult
Temple of Apollo
Temple of Aphrodite
It would be rude and blasphemous to go inside the temples and destroy them. The city would be in an uproar for anyone to defy their gods. The temples were hallow locations to be entered reverently. Paul is suggesting that my temple is not a location with a building, rather my body is the temple of the Holy Spirit so take care of it to do work in the field by planting (Paul) or watering (Apollos). When the Spirit completes the work at that Day rewards will be prescribed. The work of the Spirit is vital for a thriving relationship with God since the Spirit comprehends the thoughts God (2:11) and interprets spiritual truths to those who are spiritual.
This smart progressive culture in Corinth boasted in the wealth of knowledge. Paul warning is to not deceive myself. Do not overestimate the opinion of myself. My wisdom is fools gold in comparison to God. My witty craftiness will be caught by God because of His omniscience. Let me realize the futile thoughts of man and pursue Christ being unwilling to take pleasure in boasting in men. Who cares about Paul, Apollos, Cephas, this world, life, or death in Christ all are yours and Christ is God’s.