He couldn’t make that promise unless He was sure that God would preserve His Word. Jesus also said, “Heaven and earth will pass away, but my words will never pass away” (Matthew 24:35; Mark 13:31; Luke 21:33).
Sinabi din ni Hesus, "Mawawala ang langit at ang lupa, ngunit ang mga salita ko'y hindi magkakabula" (Mateo 24:35; Markos 13:31; Lukas 21:33).