That we ought to pour out our heart implies that it must be full of something to be emptied. Maybe right now it’s full of cares and troubles, doubts and worries, burdens and baggage. God welcomes such an offering, even more so, He anticipates it eagerly.
Lest we forget, this invitation comes at a great cost. The only plea we have before God, the only right we have to enter His presence at all, is through the death of His Son. And it is in His death that we have the solemn promise that when we enter His throne room to pour out our hearts, we will find mercy and grace in our time of need.
So let us pour out our hearts completely. Hold nothing back. Give our entire heart to Him who gave everything for us.