The Psalmists in telling everyone to praise God are doing what all men do when they speak of what they care about.
C. S. LewisTo have Faith in Christ means, of course, trying to do all that He says. There would be no sense in saying you trusted a person if you would not take his advice.
C. S. LewisAt the very least, they can be persuaded that the bodily position makes no difference to their prayers; for they constantly forget[...]that they are animals and that whatever their bodies do affects their souls.
C. S. Lewis