9 They must keep hold of the deep truths of the faith with a clear conscience. 10 They must first be tested; and then if there is nothing against them, let them serve as deacons. 1 Timothy 3:9-10
I suspect many in the early Church had trouble grasping some of the deep truths of the faith Paul was talking about. The death, burial and resurrection, the Second Coming, and the Trinity itself could have been ideas that people hd a hard time understanding. We have the benefit of 2000 years of scholarship and teaching to rely on; the early Church had very little.
Still, though, these teachings are applicable because most churches have their doctrinal statements laid out for all to see. Reading them and agreeing to them is sufficient for most.
Since we’re on that topic. Here is what is commonly called the Apostle’s Creed. It’s been the standard set of beliefs for many centuries. It’s good to review the essentials of the faith laid out in a few short sentences:
I believe in God, the Father almighty,
creator of heaven and earth.
I believe in Jesus Christ, God’s 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 to the dead.
On the third day he rose again;
he ascended into heaven,
he is seated at the right hand of the Father,
and he will come to judge the living and the dead.
I 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. Amen.