The foundation of true holiness and true Christian worship is the doctrine of the gospel, what we are to believe. So when Christian doctrine is neglected, forsaken, or corrupted, true holiness and worship will also be neglected, forsaken, and corrupted.
John OwenWe are taught in an especial manner to pray that God would give his Holy Spirit unto us, that through his aid and assistance we may live unto God in that holy obedience which he requires at our hands.
John OwenConsider who and what you are; who the Spirit is that is grieved, what he has done for you, what he comes to your soul about, what he has already done in you; and be ashamed. Among those who walk with God, there is no greater motive and incentive unto universal holiness, and the preserving of their hearts and spirits in all purity and cleanness than this: That the blessed Spirit, who has undertaken to dwell in them, is continually considering what they give entertainment in their hearts unto, and rejoices when his temple is kept undefiled.
John OwenThe vigour, and power, and comfort of our spiritual life depends on the mortification of the deeds of the flesh...The choicest believers, who are assuredly freed from the condemning power of sin, ought yet to make it their business all their days to mortify the indwelling power of sin...Do you mortify; do you make it your daily work; be always at it whilst you live; cease not a day from this work; be killing sin or it will be killing you.
John OwenWhen we realize a constant enemy of the soul abides within us, what diligence and watchfulness we should have! How woeful is the sloth and negligence then of so many who live blind and asleep to this reality of sin. There is an exceeding efficacy nad power in the indwelling sin of believers, for it constantly inclines itself towards evil. We need to be awake, then, if our hearts would know the ways of God. Our enemy is not only upon us, as it was with Samson, but it is also in us.
John Owen