Pentecost

President Joseph F. Smith suggested that none of the disciples of Jesus Christ were fully converted at the time of the Feast of the Passover, or even at the time of his crucifixion. He stated:

“To my mind it strongly appears that not one of the disciples possessed sufficient light, knowledge, nor wisdom, at the time of the crucifixion for either exaltation or condemnation; for it was afterward that their minds were opened to understand the scriptures, and that they were endowed with power from on high; without which they were only children in knowledge, in comparison to what they afterwards became under the influence of the Spirit.” (Gospel Doctrine, 5th edition, Deseret News, 1919, p. 433.)

Elder Bruce R. McConkie has suggested that the conversion of the faithful disciples, including Peter, took place on the Day of Pentecost:

“Conversion is more—far more—than merely changing one’s belief from that which is false to that which is true; it is more than the acceptance of the verity of gospel truths, than the acquirement of a testimony. To convert is to change from one status to another, and gospel conversion consists in the transformation of man from his fallen and carnal state to a state of saintliness. …

“In real conversion, which is essential to salvation (Matt. 18:3), the convert not only changes his beliefs, casting off the false traditions of the past and accepting the beauties of revealed religions, but he changes his whole way of life, and the nature and structure of his very being is quickened and changed by the power of the Holy Ghost.

“Peter is the classic example of how the power of conversion works on receptive souls. During our Lord’s mortal ministry, Peter had a testimony, born of the Spirit, of the divinity of Christ and of the great plan of salvation which was in Christ. ‘Thou art the Christ, the Son of the living God,’ he said, as the Holy Ghost gave him utterance. (Matt. 16:13–19.) When others fell away, Peter stood forth with the apostolic assurance, ‘We believe and are sure that thou art that Christ, the Son of the living God.’ (John 6:69.) Peter knew, and his knowledge came by revelation.

“But Peter was not converted, because he had not become a new creature of the Holy Ghost. Rather, long after Peter had gained a testimony, and on the very night Jesus was arrested, he said to Peter: ‘When thou art converted, strengthen thy brethren.’ (Luke 22:32.) Immediately thereafter, and regardless of his testimony, Peter denied that he knew Christ. (Luke 22:54–62.) After the crucifixion, Peter went fishing, only to be called back to the ministry by the risen Lord. (John 21:1–17.) Finally on the day of Pentecost the promised spiritual endowment was received; Peter and all the faithful disciples became new creatures of the Holy Ghost; they were truly converted; and their subsequent achievements manifest the fixity of their conversions. (Acts 3, 4.)” (Bruce R. McConkie, Doctrinal New Testament Commentary, Bookcraft Co., 1973, vol. 1, pp. 770–71.)