What is most likely the purpose of the counsellor’s metaphor in the following passage (paragraph 5, The Ecclesiastical History of the English People)?

Another of the king’s chief men agreed with this advice and with these wise words and then added, “This is how the present life of man on earth, King, appears to me in comparison with that time which is unknown to us. You are sitting feasting with your eldermen and thanes in winter time; the fire is burning on the hearth in the middle of the hall and all inside is warm, while outside the wintry storms of rain and snow are raging; and a sparrow flies swiftly through the hall. It enters in at one door and quickly flies out through the other. For the few moments it is inside, the storm and wintry tempest cannot touch it, but after the briefest moment of calm, it flits from your sight, out of the wintry storm and into it again. So this life of man appears but for a moment; what follows or indeed what went before, we know not at all. If this new doctrine brings us more certain information, it seems right that we should accept it.” Other elders and counsellors of the king continued in the same manner, being divinely prompted to do so.

a.) To distract his audience from a discussion of religion by talking instead about nature
b.) To demonstrate that he is already impacted by Christianity
c.) To link the expansive concept of faith to a relatable situation
d.) To make a comparison between winter and death

"The Ecclesiastical History of the English People" was written by the Venerable Bede around 731 AD where he describes the history of the Christian Churches in England and of England. The above passage is from Book II where he gives a description of Gregory the Great who was an early church leader. Bede goes on to give an argument about the need to convert to Christianity by giving an allegorical story of a sparrow that flies into a warm banquet hall and then flies out into the cold again. This is his argument for the kingdom of Northumbria to convert to Christianity, which gives evidence that he is already impacted by the religion himself.