We must be careful not to confound what is exclusively God's work with what is our responsibility.
It is God the Holy Spirit who leads us into enjoyment; our responsibility is to see that we do not grieve Him (Eph. 4:30).
Every Christian, whether a babe, a young man, or a father (1 John 2:13), has the blessed privilege of communion with the Father, and with His Son Jesus Christ; there is nothing higher, and it is fullness of joy (1 John 1:4).
It cannot, however, be expected that a babe should have such deep communion as a father; but he may have fullness of joy, and in time he may grow up to be a father-not by making his growth an object, but by feeding on Christ he grows (John 6:48, 57).
The moment enjoyment is pressed as an object, Christ, the true Object, is displaced.
The prayer of the Apostle (Eph. 3:14-21) was that God might so work in the saints, that they might be filled to all the fullness of God. Well may we say, "Blessed be the God and Father of our Lord Jesus Christ," who has taken up such as we are, to fill us with His fullness, and display in the ages to come, the exceeding riches of His grace in His kindness toward us by Christ Jesus.
Do not grieve that Holy Spirit of God, whereby ye are sealed unto the day of redemption (Eph. 4:30); then you will have fullness of joy, not by making joy an object, but Christ, who is everything, and in all (Col. 3:11).