Matthew 28:18-20 18 And Jesus came and said to them, All authority in heaven and on earth has been given to me. 19 Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 20 teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age.
2 Corinthians 5:18-21 18 All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation; 19 that is, in Christ God was reconciling the world to himself, not counting their trespasses against them, and entrusting to us the message of reconciliation. 20 Therefore, we are ambassadors for Christ, God making his appeal through us. We implore you on behalf of Christ, be reconciled to God. 21 For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God.
So simple it simply cannot be true to so many. They stumble at the stumblingblock.