"I never knew you."
I think the hardest words Jesus ever uttered are penned right there in Matthew 7. He made it clear that theistic name-dropping and spiritual accomplishments (even really impressive ones) weren't enough.
"Didn't we prophesy...cast out demons...do many mighty works in your name?" they ask.
"I never knew you," Jesus responds. "Depart from me..."
I picture a sadness in Jesus' tone as He speaks to these do-gooder strangers that spent their lifetime distant from the One who wanted to call them "friends."
We aren't called to something but to someone.
The last thing a loved one says before passing is usually the first thing that comes to our minds when they're remembered. Jesus' final moments with His closest followers are filled with the words that commissioned an unstoppable movement.
In Matthew 28 Jesus said, "Go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you." and that's what they did! In fact, throughout the book of Acts and Epistles, they go and do a lot of the same things seen earlier in Matthew 7. They prophesied, cast out demons, and did mighty works in Jesus' name.
So...what's the difference between the Matthew 7 "departed" and the Matthew 28 disciples?
The Great Distinction
Jesus' "Great Commission" in Matthew 28 is often incompletely consumed. (Compare it to a PBJ without bread. It's just a mess!) The charge to "make disciples" is bookended by something we can't afford to ignore.
Let's look at Jesus' words in full context...
“All authority in heaven and on earth has been given to me. 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, teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age.”
"All authority..." - Jesus begins by stating His position, giving the disciples a clear understanding of where their source of power came from.
"I am with you always..." - Jesus concludes by assuring them of His constant presence.
Jesus' position and presence were what empowered His followers to see the charge fulfilled. It was the knowing that sustained the going.