This resolution is one of the foundational documents of the Israeli-Arab peace process, to which all future resolutions refer. However, it is so vague and its definition so contested - even after forty years - that it amounts to little more than an empty plea.
The resolution does not even mention the Palestinians and does not call for the establishment of a Palestinian state; the first Security Council resolution to do that, 1397, was only passed - thanks to the Bush administration - in 2002. The resolution calls for Israel to withdraw from occupied territory in exchange for "secure and recognized boundaries" and recognition. This was novel because in 1967, not one Arab state had recognized Israel's right to exist. However, the resolution makes clear that the deal on offer was not "land for peace", but "land for secure boundaries".
Israel's boundaries have not been secure since 1967 and so, even when the political will to get rid of the territories emerged in Israel, doing so proved harder than it looked. No Israeli government can hand the territories over to a Palestinian state - as is now presumed to be the solution, as Jordan and Egypt do not want the lands back, contrary to this resolution's suggestion - unless they are guaranteed these secure boundaries. The resolution also makes clear they are not expected to do so, and the UN has never called for an unconditional withdrawal.
While on the one hand this reflects the consensus-inspired wording typical of UN resolutions, it also highlights a more pertinent truism: without secure borders for every country in the region, including Israel, there can be no lasting peace. The acquisition of territory by force may be inadmissable, but so is a life under constant threat. Sustainability must lie at the heart of any solution.