In his last words, Jesus was communicating that the world - He said, "Tetelestai" - which means, he has completed, what He came to accomplish.

• The task of earning the salvation of this mankind was completed with this work on the cross.

The Book of Hebrews (Hebrews 9:12, 26)  describes how Jesus was the ultimate Lamb of God and by his sacrifice, the work of forgiveness was finally complete.

He did not enter by means of the blood of goats and calves; but he entered the Most Holy Place once for all by his own blood, having obtained eternal redemption…

But now he has appeared once for all at the end of the ages to do away with sin by the sacrifice of himself