One way of characterising the two ways of living is by a picture of marriage, as Paul does in Romans 7:1-6. He paints a picture of law marriage which bears fruit for death and stirs up sinful passions. By contrast a Christ marriage bears fruit for God and is the new way of the Spirit from the husband who was raised from the dead.
Translate this into having an evening meal with two couples. What would it be like to have dinner with Mr & Mrs Law? What would it be like to spend the evening with 'The Christ's"?
An evening with The Law's would surely be very stressful, you'd be worrying whether you're using the right cutlery and saying the right things, your hosts always worrying about whether you're happy or whether they've left anything in the oven, it'd all be about keeping up the etiquette. You'd be checking your watch often to find a moment to excuse yourself.
Meanwhile spending an evening in the Christ household would surely be refreshing and life-giving. The time would fly by as the stimulating conversation revitalises you just as the food does. The food might well not be so fancy but the absence of a stuffy and heavy atmosphere makes it taste so good.
The question is - what kind of household is your church, your home group, your home, your CU like? Where would you want to spend the evening?
How do you change from one marriage to the other? The only way to end a marriage is by death. The law wont die so we need to die, and with Christ we can die - and then rise married to him. The answer to change your household is to get to the cross of Christ - to get after the gospel, after the Spirit, to be a people of faith rather than trying and doing.
More on Romans 7 from Richard Walker