Seeing a cardinal out your window is not unusual and will have a particular which means, relying on what you are going by means of. Any of the aforementioned meanings should still apply, however the window is exclusive in that the cardinal is showing to you in your house.
Our properties are our protected areas and our havens from the world. For a cardinal to indicate up there for you may point out a must faucet into your personal vitality and energy to maintain your property (and subsequently, your personal aura) protected and safe. Perhaps which means setting firmer boundaries, working together with your root chakra as beforehand talked about, or dealing with any fears you have been avoiding.
Again, as Charles explains, you may at all times instantly ask/invite a cardinal to work with you and share its messages, to get a greater understanding of what it is attempting to inform you. And from there, you may heed its message and take acceptable motion.