1Pet. 3:7 Likewise, husbands, live with your wives in an understanding way, showing honor to the woman as the weaker vessel, since they are heirs with you of the grace of life, so that your prayers may not be hindered.
This verse is not saying something mystical about how your prayers are hindered; rather, it is eminently practical. For, it is hard to sit down at breakfast when you are angry with your wife and say thanksgiving to the God of the Universe for the food. And the kids are not naive enough to miss that dad is having a hard time praying when he is angry at mom.