This is one of John Donne's Holy Sonnets, that explore and describe the relationship of the poet with his maker. In particular, this poem describes the way in which a new life can be begun through God's gift of grace. It is important to focus on the way that the speaker, as a sinful man, is presented. The figures of speech that are used present him as one who is helplessly sinful and who, by his own strength, is unable to change this situation. Thus it is that the speaker describes himself as being "betrothed unto your enemy."
Such descriptions yield some immensely powerful paradoxes that describe the need of the speaker for God's grace and to highlight the various paradoxes that lie at the heart of the Christian creed, such as life only being possible through death. Thus the last three lines capture the essence of such paradoxes as they present the appeal of the speaker to God:
Take me to you, imprison me, for I
Except you enthrall me, never shall be free,
Nor ever chaste, except you ravish me.
Paradoxically, the human sinner is so sinful and trapped in his position that he needs to be imprisoned to be truly free and "ravished" to be "chaste." Thus the sonnet explores the concept and process of spiritual regeneration as the soul is only able to be given life through the grace of God. Note how the passive nature of the speaker and his urgings to God to enact this process, with some violence, both reinforce the plight of the speaker's condition and the way that such regeneration can only come from God alone and his grace.