Answer: Everything taught to us in the gospel. The Apostles’ Creed expresses what we believe in these words: We believe in God the Father Almighty, Maker of heaven and earth; and in Jesus Christ his only Son our Lord, who was conceived by the Holy Spirit, born of the virgin Mary, suffered under Pontius Pilate, was crucified, died, and was buried. He descended into hell. The third day he rose again from the dead. He ascended into heaven, and is seated at the right hand of God the Father Almighty; from there he will come to judge the living and the dead. We believe in the Holy Spirit, the holy catholic church, the communion of saints, the forgiveness of sins, the resurrection of the body, and the life everlasting.
Scripture: Jude 1:3 Beloved, although I was very eager to write to you about our common salvation, I found it necessary to write appealing to you to contend for the faith that was once for all delivered to the saints.
Source: New City Catechism