In his seminal message at Caesarea, Peter preached Christ to unsaved Gentiles by declaring “how God anointed Jesus of Nazareth with the Holy Ghost and with power: Who went about doing good and healing all that were oppressed of the devil; for God was with Him” (Acts 10:38). This statement confronted Cornelius and those who were with him with testimony to God the Father, Jesus, and the Holy Ghost. These unsaved Gentiles therefore were put in a position of having to believe an evangelistic message that testified not just to the deity of Jesus, but also to God who anointed Him with the Holy Spirit.
Peter’s evangelistic Trinitarian testimony to Christ did not hinder his hearers from getting saved; in fact, all of them were saved (10:44)! From this account, therefore, we should learn that instead of thinking that we have to keep the message simple by talking only about Jesus, we should witness to people by presenting Him rightly as the Christ by relating Him to both the Father and the Spirit.
Undoubtedly, we would enhance our proclamation of the gospel by doing so!