There is no sermon given by the apostles that teach penal substitution. For example on the day of pentecost people were saved because they believed the sermon' s main point that Jesus is the Messiah , the sermon was not about penal substitution (Jesus died in place of you) . It is just that clear, salvation is through faith -the revealed truths of God James 1:18 & 21 Of his own will begat he us with the word of truth, that we should be a kind of firstfruits of his creatures. 21 Wherefore lay apart all filthiness and superfluity of naughtiness, and receive with meekness the engrafted word, which is able to save your souls. Abraham was saved by the word: Genesis 15:1,4,5,6 1 After these things the WORD of the Lord came unto Abram in a vision, saying, Fear not, Abram: I am thy shield, and thy exceeding great reward. 4 And, behold, the WORD of the Lord came unto him, saying, This shall not be thine heir; but he that shall come forth out of thine own bowels sh...