ACROSS
 8. <Jesus> EMMANUEL ⇐ EMMA + ←LE UN←
 9. <Santa's reindeer> DONNER | (..e)D ON NER(d..)
11. MIN + CE ⇒ MINCE <festive fruit and spices>
12. ECONOMIST* | EMOTICONS <symbolic expressions>
13. <took lead> PIONEERED ⇐ ONE inside PIE + RED
15. <inexperienced> GREEN | GEN outside RE
16. (C-LIST FOLK SINGER)* | STOCKING FILLERS <minor Christmas pieces>
18. EG Y + _P _T | EGYPT <land>
20. K inside RESTRICT* | TRICKSTER <fraud>
22. <standard> TRICOLOUR | TOUR outside RI COL
23. [-b]LIGHT[-y] = LIGHT <sunny>
25. (GRAN HE)* = REHANG <put up secondhand tinsel?>
26. ALL + ←_A_I_U_ L_E_← | ALLELUIA <praise for God>

DOWN
 1. <partner> TEAM UP | T_E ←PUMA←
 2. MEN after O_ | OMEN <the Star of Bethlehem?>
 3. <thoughtless> KNEE-JERK ⇐ K NEE[-d] JERK[-y]
 4. PER INGRATE* I + ON | PEREGRINATION <pilgrimage>
 5. BONG outside XI | BOXING <sport>
 6. (I CHEER ON)* NT | INCOHERENT <rambling>
 7. <gifts> PRESENTS = PS outside RESENT
10. <jester hosting Christmas feast> LORD OF MISRULE / (DOLEFUL MORRIS)*
14. <carol> O HOLY NIGHT | OHO LYING* HT
16. <be stunned> SEE STARS = SEER'S outside ST A_
17. KILLER* outside IE | LIKELIER <less remote>
19. <awkward> THORNY | THOR + N_Y
21. <ceremony> RITUAL ⇐ _RI_ _TU_ + _AL_
24. <bauble> GAUD | DUG* outside A_