set in concrete

established etched in stone firm immutable permanent set in stone unchangeable

absolute binding carved in stone compulsory conclusive decisive dictated exacting final inflexible irrevocable mandatory set unalterable unbending written

immobile immutable impassive inflexible motionless stationary steadfast uncompromising unshakable unyielding

adamant constant fast firm set solid stable

dead set on dug in hard-nosed immotile intransigent locked-in obdurate quiescent resolute rooted secure set in stone standpat stick to guns stuck unalterable unchangeable unmodifiable unwavering

flexible mobile moving unfixed willing yielding

changeable inconstant indefinite loose movable soft supple undecided unstable untrustworthy wavering

durable enduring long-lasting perpetual stable

everlasting invariable perennial set

abiding changeless continual diurnal fixed for keeps forever forever and a day immutable imperishable in for the long haul indestructible perdurable perduring persistent set in stone steadfast unchanging unfading

temporary

changing

ephemeral