sinteins

[ sin- ← Prot-Germ *sem-; used in O German languages as a prefixed component of compound words in the sense of: “always, continually”; cf OE sin-dréam “eternal joy / mirth”; sin-niht “eternal night / darkness”; O Sax sin-líf “eternal life”; sin-grōna “evergreen”; OHG sin-gruoni “evergreen”; O Icel sí-grænn “evergreen”; sí-glaðr “always glad / joyful”;
-teins ← Prot-Germ *tīnaz ← Indo-Europ *dein-; cf Sanskr dina- “day”; Lat peren-dinus “the day after tomorrow”; Lith dienà “day”; O Prus dienan “day”; O Slav дьнь “day” (Russ день)]

sinteinan - Acc, sing, masc - Matth. VI, 11
sinteinom - Dat, pl, fem - Skeirns. III, 6

2.1. (a)

strong declension of adjectives -a- (-o-)* stem blinds (blind)
singular number
	masculine gender	neuter gender	feminine gender
nominative	blinds	blind, blindata	blinda
genitive	blindis	blindis	blindaizōs
dative	blindamma	blindamma	blindai
accusative	blindana	blind, blindata	blinda
plural number
	masculine gender	neuter gender	feminine gender
nominative	blindai	blinda	blindōs
genitive	blindaizē	blindaizē	blindaizō
dative	blindaim	blindaim	blindaim
accusative	blindans	blinda	blindōs

* By the -o- stem versions we mean fem forms of the same type of adjectives.