The clip comes from the SpongeBob SquarePants episode Tea at the Treedome, first aired in 1999, where SpongeBob visits Sandy's air-filled home and slowly dries out without water. Trapped by politeness, he insists he does not need water while visibly wilting. The scene became a lasting reaction meme online, clipped and reposted for moments of denial and temptation, because his escalating delivery sums up pretending not to want something everyone can see you need.
About this sound
Spongebob saying I don't need it while staring at water from the cartoon, used as a meme sound for resisting temptation and pretending you are fine.
This is Spongebob repeating I don't need it in a strained, increasingly desperate voice while looking at a glass of water he claims he can live without. His delivery starts controlled and self-assured, then wavers as the temptation builds, turning a simple line into a clear picture of someone trying to convince himself. The humor comes from that collapse in confidence, because the voice alone tells you he absolutely does need it, making the clip instantly recognizable even without the scene playing.