John Gill Commentary 1 Kings 8:37

"If there be in the land famine, if there be pestilence, if there be blasting [or] mildew, locust [or] caterpillar; if their enemy besiege them in the land of their cities; whatsoever plague, whatsoever sickness there be;" — 1 Kings 8:37 (ASV)

Ver. 37 If there be in the land famine
Through want of rain, or any other cause, as there had been a three years' famine in the time of David, and it is supposed it might be again, though Canaan was a land flowing with milk and honey:

if there be pestilence ;
as there had been, for David's numbering the people:

blasting ;
or blights, occasioned by the east wind:

mildew ;
a kind of clammy dew, which falling on plants, corn corrupts and destroys them, see (Amos 4:9) ,

locust ,
or

if there be caterpillar ;
creatures very pernicious to the fruits of the earth, and cause a scarcity of them, see (Joel 1:4) ,

if their enemy besiege them in the land of their cities ;
so that they cannot go out to gather the increase of the earth, or till their land:

whatsoever plague, whatsoever sickness there be ;
whatever stroke from the hand of God, or what judgment or calamity soever befalls.