Contradiction with James 2:24
This verse states that a person is justified by works and not by faith only, which contrasts with Acts 18:8 that emphasizes belief in the Lord.
James 2:24: Ye see then how that by works a man is justified, and not by faith only.
Contradiction with Acts 10:44-47
These verses describe the Holy Spirit falling on believers before baptism, which contrasts with Acts 18:8 where baptism follows belief.
Acts 10:44-47: While Peter yet spake these words, the Holy Ghost fell on all them which heard the word.