Slightly revised version of what I wrote earlier:
> --- In norse_course@yahoogroups.com, "llama_nom" <600cell@...> wrote:
>
> In pre-literarary times, there was tendency to devoice final 'd' to
> 't', and 'g' to 'k'. The resulting combinations 'nt' and 'nk' were
> then affected by a tendency to assimilate a nasal to a following
> voiceless stop, hence the sg. imperative 'statt (þú)' < *'stant' <
> *'stand', and 'bitt (þú)' (beside the analogical 'bind (þú)'). See
> Gordon §§ 73 and 77.
These sound-changes were no longer operative when Old Norse was being
written in manuscripts, and by then a lot of examples had been
restored by analogy with other parts of the paradigm, hence "ek
stend", 'ek geng', etc.