a) "We have taken the sword of Caesar and in taking it, of course, have rejected Thee and followed him ."
The "thee" in the above quote refers to Christ. Placing Caesar and Christ in this sentence refers to central dichotomy of religion between religion and the state. They are also used in a symbolic sense, with Caesar being representative of earthly power and wealth, and Christ representing power and wealth in heaven. According to scripture, it is better to forego everything that the earth offers in favor of an eventual award.
The Christ figure in the story displays a calm that emerges from heavenly power. He is unperturbed by the power of earthly kings and, true to his nature, continues to speak words only according to what he believes is right. He chooses heavenly power.
In terms of religion and psychology, the choice between religion and politics occurs concomitantly with the one between earthly and heavenly wealth. Choosing one necessarily precludes choosing the other. Hence, most people tend to ignore religion in favor of earthly comfort, especially during an era that is very materially oriented.
b) "The kiss glows in his heart but the old man adheres to his idea."
The key idea in this quote is the fact that the man is old. As such, he has lived a lifetime according to a certain paradigm. Because of this his existing beliefs and qualities are very difficult to change. – old. No matter how strongly actions affect him, his core beliefs and personality are very unlikely to change. This is especially so during the sixteenth century, the time period of the story. Personal change and empowerment tended to be discouraged, mostly by means of violence or threat of punishment.
In terms of religion and psychology, An old man is conditioned throughout a lifetime of indoctrination, both in terms of religion and otherwise. A child for example grows up in a parental home where a certain religion is pra...