The following is from a message entitled Mortifying Sin By The Holy Ghost preached by David Martyn Lloyd-Jones (1899-1981)
"The term mortify really explains itself. 'To mortify' is to deaden, to put to death…so the exhortation is that we must 'deaden,' put an end to the 'deeds of the body.' This is the great New Testament exhortation in connection with sanctification from the practical standpoint, and it is addressed to all Christian people.
How is this work to be done?...The Apostle makes it plain. 'If ye through the Spirit do mortify the deed of the body' – 'through the Spirit'! The Spirit is mentioned particularly, of course, because His presence and His work are the particular and peculiar mark of true Christianity. This is what differentiates Christianity from morality, from 'legalism' and false Puritanism – 'through the Spirit'! The Holy Spirit, as we have seen, is in us as Christians. You cannot be a Christian without Him. If you are a Christian, the Holy Spirit of God is in you, and He gives us power. He 'mediates' to us the great salvation the Lord Jesus Christ has worked out for us and enables us to work it out. The Christian must therefore never complain of want of ability and power. For a Christian to say, 'I cannot do it' is to deny the Scriptures. A man who has the Holy Spirit residing in him must never utter such an expression: it is a denial of the truth concerning him . . . .
But how does this work out in practice?...To begin, we have to understand our position spiritually, for many of our troubles are due to the fact that we do not realize, and do not remember, who we are and what we are as Christians. People complain that they have no power, and that they cannot do this or that. What they really need to be told is not that they are absolutely hopeless, and that the must 'hand it over,' but, rather, what all Christians are told in the 1st chapter of the Second Epistle of Peter in verses 2 to 4: 'Grace and peace be multiplied unto you through the knowledge of God, and of Jesus our Lord, According as his divine power hath given unto us all things that pertain unto life and godliness.'
Everything that 'pertains unto life and godliness' has been given us 'through the knowledge of him that hath called us to glory and virtue.' And again: 'Whereby are given unto us exceeding great and precious promises: that by these [by means of these exceeding great and precious promises] ye might be partakers of the divine nature, having escaped the corruption that is in the world through lust.'
Yet Christian people moan and complain that they have no strength. The answer to such people is 'All things that pertain to life and godliness have been given you. Stop moaning and grumbling and complaining. Get up and use what is in you. If you are a Christian the power is in you by the Holy Spirit; you are not hopeless.' But the Apostle Peter does not leave it at that. In the ninth verse of that same chapter of his second Epistle, he says, 'He that lacketh these things' – in other words, the man who does not do the things he has been exhorting him to do – 'is blind and cannot see afar off.' He is shortsighted, 'and has forgotten that he was purged from his old sins.' He has not got a true view of the Christian life. He is talking and living as if he were still unregenerate. He says, 'I cannot continue as a Christian; it is too much for me.' Peter urges such a man to realize the truth about himself. He needs to be awakened; he needs to have his eyes opened and his memory refreshed. He needs to be up and doing, instead of moaning over his deficiencies.
Furthermore, we have to realize that if we are guilty of sin we are 'grieving the Holy Spirit of God' Who is in us. Every time we sin, it is not so much that we sin and become miserable that chiefly matters, but that we are grieving the Holy Spirit of God Who is dwelling in our body. How often do we think of that? I find when people come to be about this matter they always talk about themselves – 'my failure.' 'I am constantly falling into this sin.' 'This sin is getting me down.' They talk about themselves. They do not talk about their relationship to the Holy Spirit, and for this reason: the man who realizes that the main trouble about his sinful life is that he is grieving the Holy Spirit, stops doing so at once. The moment a man sees that that is his real problem, he deals with it. He is not longer chiefly concerned about his own feelings; when he realizes that he is grieving the Holy Spirit of God, he takes immediate action."
The italics were found in my copy of the message and reproduced accordingly. I highlighted the points of importance to me by changing the color.
This really caught my attention because I have been saying for years we have the Holy Spirit living in us and we have all the power we need to do everything we should. God lives in us. We are his temple. The fullness of God's omnipotence is available to us to aid us in being what we should be. "I can't" should be "I won't."