An Etymological Dictionary of the German Language/fürchten
fürchten, ‘to fear, dread,’ from MidHG. vürhten (pret. vorhte), OHG. furihten, forahtan (pret. forahta), ‘to be afraid’; comp. OSax. forahtjan, AS. forhtian; Du. and Scand. are wanting; Goth. faurhtjan, ‘to fear, be afraid,’ with the partic. faúrhts, ‘timid,’ used as an adj. The dental of the vb., which was probably strong orig., is a suffix of the present stem, hence Teut. farh-tjan; the corresponding abstr. OHG. forh-ta is formed like Schande. To the Teut. root forh (Aryan prk?, qerk?), Lat. querquerus, ‘shivering,’ and Gr. καρκαίρω, ‘to tremble,’ have been allied.