What do people mean when they say "works"won't get you to heaven?

Philippians 2
5In your relationships with one another, have the same mindset as Christ Jesus: 6Who, being in very nature[a] God, did not consider equality with God something to be used to his own advantage; 7rather, he made himself nothing by taking the very nature[b] of a servant, being made in human likeness. 8And being found in appearance as a man, he humbled himself by becoming obedient to death— even death on a cross!

Excerpt form a devotion:
AND CAN IT BE? by Kevin Twit 
 In 1738, Charles Wesley was struggling to find peace with God. He had served as a missionary to Georgia, but that had turned out disastrously bad. Peter Bohler, the leader of the London Moravians, asked Charles if he hoped to be saved. Charles replied that he did. Bohler pressed, “Upon what basis do you hope to be saved?” Wesley said, “Because I have used my best endeavors to serve God.” Bohler shook his head sadly and walked away. 

 Wesley recorded his reaction in his journal: “What, are not my endeavors a sufficient ground of hope? Would he rob me of my endeavors? I have nothing else to trust to.”

God requires that we love Him perfectly from the moment we are born until the moment we die, with no lapses. Faced with this impossible requirement, many religious people attempt to take solace in such empty hopes as our best, though imperfect, endeavors. But this hymn points us to a higher ground of hope—the power of the gospel. 

 Later in 1738, Wesley’s friend, John Bray, discovered Martin Luther’s Commentary on Galatians and brought it to Wesley, who was sick in bed. Luther had famously once said that the whole of the gospel was found in the personal pronouns, and Wesley found peace as the Lord gave him faith to believe that Jesus had died for him. Wesley wrote in his journal, “I spent some hours this evening in private with Martin Luther, who was greatly blessed to me, especially his conclusion of the second chapter. I labored, waited, and prayed to feel ‘Who loved me and gave Himself up for me.’” 

 It is sometimes said that “And Can It Be” was Wesley’s first hymn, written soon after his conversion. Hymn scholars are now convinced that “Where Shall My Wondering Soul Begin?” was actually his first hymn. But “And Can It Be” was written soon after and expresses beautifully and powerfully the converting power of the gospel that he had experienced. Wesley is one of our most skilled hymn writers. He begins with a piercing question to which no real answer can be given: “How can it be, that thou my God, shoulds’t die for me?” If we ever get to the point where God’s grace seems deserved or expected, we are in deep trouble. 

 We see Wesley’s grasp of Luther’s point in his use of personal pronouns: “my God,” “for me.” But it is in the last verse where Wesley reveals the heart of his new-found hope. “Alive in Him, my living head, and clothed in righteousness divine.” 

 Wesley had come to understand that the gospel Christ gives us is what God requires—His perfect righteousness through our union with Him. What Christ does, we get credit for; what He deserves, we get! Rather than trusting in our best endeavors, Wesley gives us words to praise God for our only true hope, the righteousness of Christ imputed to His people through faith. This brings us not only hope, but boldness to claim the crown—not because of what we have done, but because of what Christ has done in our place.

And Can It Be That I Should Gain? Charles Wesley, 1738

 And can it be that I should gain An interest in the Savior’s blood? Died He for me, who caused His pain— For me, who Him to death pursued? Amazing love! How can it be, That Thou, my God, shouldst die for me? Amazing love! How can it be, That Thou, my God, shouldst die for me?

...No condemnation now I dread; Jesus, and all in Him, is mine; Alive in Him, my living Head, And clothed in righteousness divine, Bold I approach th’eternal throne, And claim the crown, through Christ my own. Bold I approach th’eternal throne, And claim the crown, through Christ my own

So, now you know thatworks do not get us to heaven. Only faith in Jesus Christ gets us to heaven. That is it, nothing more and nothing less!

I praise you Father, that you made it simple for us to be with you for eternity. Please keep us focused on this and not what we do that is good. Amen.