Midrasch zu Könige I 1:34

(Fol. 13b) Our Rabbis were taught: If it happened that he, his teacher and his father were in captivity [and he was able to redeem only one] he himself has the preference over the teacher, and his teacher has the preference over his father. His mother, however, has the preference over all. A sage has the preference over a king of Israel, for if a sage dies, we have no equal to him, but if a king dies all Israel is fit for the throne. A king has the preference over a High-priest, as it is said (I Kings 1, 33) Take with you the servants of your lord. A High-priest has the preference over a prophet, as it is said (Ib.) And let Zadok the priest with Nathan the prophet, hence the priest precedes the prophet, and there is another passage (Zech. 3, 8) Hear now, O Joshua the High-priest, thou and thy fellows, etc. One might say that they were ignorants therefore the priest precedes them. The verse therefore says (Ib.) For they are men that are a sign (Mofeth). The word Mofeth is applied to prophecy, as it is said (Deut. 13, 2) And he gives thee a sign (Mofeth) or a wonder.