How do you know that the person repeating after you actually understands and believes in the resurrection? Repeating after you does not prove anything. If they want to be saved they will say anything you instruct them to say. Will they even remember what they said the next day?
Sounds like you are referring to dictating a sinners prayer when you say, "repeating after me".
I don't do that, it doesn't prove anything. The Lord is salvation. My words are my faithfulness
to the Lord. I don't speak because my words save people. I speak out of obedience to my Master.
I include the resurrection when I share the simplicity of the Gospel because all the apostles did so.
As the OP explains, rebuking His closest disciples for not believing the report of His resurrection was
the first order of business after He was raised. It is about believing the Word of God. How can
you be faithful and not state what you believe? I believe that God raised His Son "according to the
scriptures" to prove His claim to be the Son of God, for which He was crucified in the first place.
"In a nutshell" Let's find a basic statement of the Gospel for believing.
1 Corinthians 15:
1 Moreover, brethren, I declare to you the gospel
which I preached to you, which also you received and in which you stand,
2 by which also you are saved, if you hold fast that word which I preached to you—unless you believed in vain.
3 For I delivered to you first of all that which I also received: that Christ died for our sins
according to the Scriptures,
4 and that He was buried, and
that He rose again the third day according to the Scriptures.
Wow! That's it? Isn't everyone who posts on this forum supposed to be accountable
to a basic Creed?