Peter's word in Acts 10:14, "By no means, Lord, for I have never eaten anything common and unclean," is also clearly not the word spoken by God, but the word spoken by Peter according to his religious concept concerning eating the unclean animals (contacting and receiving the unclean Gentiles).
Peter's word here was stopped by the voice from heaven, saying, "The things that God has cleansed [the Gentiles whom God sanctifies], do not make common" (v. 15).
This stopping word indicates that Peter, even as the first apostle in the New Testament who followed the Lord for three and a half years and experienced Pentecost by speaking a very clear word, witnessing to Christ in His death and resurrection which produced the first church in Jerusalem, still was vague in the divine revelation concerning the spreading of the gospel for Christ's increase from the Jews to the Gentiles, as what the Lord told him and the other disciples in Acts 1:8. This stopping word also indicates that God would confirm Peter's visit to Cornelius, a Roman centurion, for the spreading of the gospel from the Jews to the Gentiles.
Peter's word was spoken according to his revelation concerning God's Old Testament economy which was very much below the standard of God's revelation concerning His New Testament economy, yet it was written by Luke in Acts under the inspiration of the Spirit of God to enlighten Peter and all the believers in the age of grace that God's gospel is not merely for the Jews but for the Gentiles unto the uttermost part of the earth also.
The above three illustrations of Peter recorded in the Scriptures under the inspiration of the Spirit of God are like three lamps shining over the believers in their darkness that they may be enlightened to see clearly that the believers in Christ as His followers should not remain in their natural self but should take up the cross to have themselves conformed to the death of Christ that Christ may live in them and that they may live with Christ, walk with Christ, and work with Christ for the producing and building up of the Body of Christ which consummates the New Jerusalem as God's ultimate goal. Also, the believers in Christ as His close followers should appreciate and exalt Christ in His preeminent person and in His most high commission as the beloved Son of the Father in whom is the Father's delight, according to God's New Testament economy, above Moses and his ministry of law and above Elijah and his ministry of the prophets, who were on the lower level of God's eternal economy. Furthermore, the believers in Christ as His witnesses should not limit the spreading of His gospel only in the circle of the Jews, but they should spread it for His unlimited increase (John 3:29-30) to all the Gentiles unto the uttermost part of the earth for the producing of the universal Body of Christ as the fullness of Christ, who fills all in all (Eph. 1:23).