P Lv23:32 :ܡܢ ܪܡܫܐ ܘܥܕܡܐ ܠܪܡܫܐ܂ ܐܫܒܬܘ ܫܒܝ̈ܟܘܢ‏ : observe your Sabbaths from evening to evening
See the entire entry for šbt vb. to observe the sabbath