Declension table of ?śāsta

Neuter	Singular	Dual	Plural
Nominative	śāstam	śāste	śāstāni
Vocative	śāsta	śāste	śāstāni
Accusative	śāstam	śāste	śāstāni
Instrumental	śāstena	śāstābhyām	śāstaiḥ
Dative	śāstāya	śāstābhyām	śāstebhyaḥ
Ablative	śāstāt	śāstābhyām	śāstebhyaḥ
Genitive	śāstasya	śāstayoḥ	śāstānām
Locative	śāste	śāstayoḥ	śāsteṣu

Compound śāsta -

Adverb -śāstam -śāstāt