G2121–εὔκαιρος–eukairos

And when a convenient day had come, that Herod on his birth-day made a supper to his lords, high captains, and chief men of Galilee;

εὐκαίρου eukairou “opportune”

Let us therefore come boldly to the throne of grace, that we may obtain mercy, and find grace to help in time of need.

εὔκαιρον eukairon “in time of need”