You will show me the path of life; in Your presence is fullness of joy; at Your right hand are pleasures forevermore. (Ps. 16:11)
After the resurrection, when Jesus was telling his disciples what to expect, Jesus promised that
"If anyone loves Me, he will keep My word; and My Father will love him, and We will come to him and make Our home with him."
What Jesus is teaching them and us, is that when we accept Jesus, the WE - the Triune God - Father, Son, and Holy Spirit comes to make Their home in believers - to abide in us.
Abide refers to an on-going, never-ending positional relationship in which one cannot be separated from the other. What a wonderful description of what happens when the "God-shaped" vacuum in our lives is filled with God - the Father, Son and Holy Spirit.
Imagine with me the top of a pie divided into three equal sections. Let's give a name to each part - body, soul and spirit. God created us to be in three parts, but sin has separated us from Him and our spirits are dead, so when we are born into this world we are only alive in body and soul.
Scripture also teaches that when Jesus comes into our being, that dead portion, the spirit, is "quickened" - made alive, so we are fully the tri-part being that God created us to be, fully in His image.
When we accept Jesus, God's own presence becomes part of us, and with that presence comes fullness of joy.
Psalm 51:10-12 says, 10 Create in me a clean heart, O God, and renew a steadfast spirit within me. 11 Do not cast me away from Your presence, and do not take Your Holy Spirit from me. 12 Restore to me the joy of Your salvation, and uphold me by Your generous Spirit.
This Psalm of Penitence arises when Nathan, the prophet, was sent to David to hold him accountable for his sin with Bathsheba. David indeed recognized that his sin was against God alone - that he had willfully sinned and broken his fellowship with God, and he asked God for restoration.
David also knew what pleased God, as he states in verses 16-17. 16 For You do not desire sacrifice, or else I would give it; You do not delight in burnt offering. 17 The sacrifices of God are a broken spirit, a broken and contrite heart - these, O God, You will not despise. Whenever we sin, and break our fellowship with God, a broken and contrite heart is all we need to lay before God. He will forgive, and restore to us the joy of His salvation. We will again be able to fully experience His presence.