16th century, equivalent tobe- +ja(“yes”) +-en (with-h- as orthographic hiatus breaker). While the verb may have been derived directly from the interjectionja, an alternative possibility is that it is a reinterpretation ofMiddle High Germanbejëhen(“to acknowledge, admit”), fromjëhen(“to say”). The according spellingbejähen is indeed attested in the 17th century.
bejahen (weak,third-person singular presentbejaht,past tensebejahte,past participlebejaht,auxiliaryhaben)
| infinitive | bejahen | ||||
|---|---|---|---|---|---|
| present participle | bejahend | ||||
| past participle | bejaht | ||||
| auxiliary | haben | ||||
| indicative | subjunctive | ||||
| singular | plural | singular | plural | ||
| present | ichbejahe | wirbejahen | i | ichbejahe | wirbejahen |
| dubejahst | ihrbejaht | dubejahest | ihrbejahet | ||
| erbejaht | siebejahen | erbejahe | siebejahen | ||
| preterite | ichbejahte | wirbejahten | ii | ichbejahte1 | wirbejahten1 |
| dubejahtest | ihrbejahtet | dubejahtest1 | ihrbejahtet1 | ||
| erbejahte | siebejahten | erbejahte1 | siebejahten1 | ||
| imperative | bejah (du) bejahe (du) | bejaht (ihr) | |||
1Rare except in very formal contexts; alternative inwürde normally preferred.