Folks, let me also add my comment (likely with my usual errors in english) ...

Tam necessario tempore, necessaria re coactus and, since restat locus huic disputationi maxime necessarius, hence I think heac necessarium est proloquor you see what I found on my dictonary about the necessitas... :)

Necessarius, a, um - adjective, comparitive necessarior

1. necessary, inevitable, ineluctable: necessaria mors, natural death (Cicero)
2. urgent, critical: tam necessario tempore, in such critical circumstance (Caesar); necessaria re coactus, forced by necessity (Caesar)
3. necessary, indispensable: omnia quae sunt ad vivendum necessaria, all that is indispensable to live (Cicero); est senatori necessarium nosse rem publicam, for a senator it is indispensable the knowledge of the administration of the State (Cicero); necessaria, orum, life needs: sua necessaria post illus honorem ducebant, they was placing their own interest after his election (Sallustius); the necessary things, the necessary, to live
4. relation, connection, relative: homo tam necessarius, a so close relative (Nepote); restat locus huic disputationi maxime necessarius, it remains a matter strictly connected with this debate (Cicero); haec necessarium fuit proloqui, it had been necessary to allow (Seneca) [necesse + -arius]

Necessarius, ii - male

1. relative, friend, patron, client: (Cicero) [see necessarius adj.]