Middle English prikke, "pointed object, something that punctures or stabs; sting of an insect; a goad; a pin or fastener; a pricking as a bodily pain or torment," from Old English prica (n.) "sharp point, puncture; minute mark made by sticking or piercing; particle, very small portion of space or time." It is a common word around the North Sea Germanic tongues (compare Low German prik "point," Middle Dutch prick, Dutch prik, Swedish prick "point, dot") of unknown etymology (compare prick (v.)).
The figurative sense of "a goad" (to the affections, the conscience, etc.) was in Middle English. The meaning "pointed weapon, dagger" is attested from 1550s.
Prick had entwined extended senses in Middle English and early modern English, such as "a point marking a stage in progression," especially in the prick "the highest point, apex, acme;" and from the notion of "a point in time," especially "the moment of death" (prike of deth).
The use in kick against the pricks (Acts ix.5, first in the translation of 1382) probably is from sense of "a goad for oxen" (mid-14c.), which made it a plausible translation of Latin stimulus: advorsum stimulum calces was proverbial in Latin, and the English phrase also was used literally. The notion in the image is "to balk, be recalcitrant, resist superior force."
The noun also was used in the 1384 Wycliffe Bible in 2 Corinthians xii.7, where the Latin is stimulis carnis meæ:
And lest the greetnesse of reuelaciouns enhaunce me in pride, the pricke of my fleisch, an aungel of Sathanas, is ʒouun to me, the which boffatith me.
The earliest recorded slang use for "penis" is 1590s (Shakespeare puns upon it). The verb prick was used in a figurative sense "have sexual intercourse with" (a woman) in Chaucer (late 14c.). My prick was used 16c.-17c. as a term of endearment by "immodest maids" for their boyfriends. As a term of abuse to a man, it is attested by 1929. Prick-teaser is attested from 1958.