Hebrews 3:13

3:13 But exhort one another each day, as long as it is called “Today,” that none of you may become hardened by sin’s deception.

Hebrews 10:25

10:25 not abandoning our own meetings, as some are in the habit of doing, but encouraging each other, and even more so because you see the day ¹  drawing near. ² 

[10:25]  ¹ sn The day refers to that well-known time of Christ’s coming and judgment in the future; see a similar use of “day” in 1 Cor 3:13.

[10:25]  ² tn This paragraph (vv. 19-25) is actually a single, skillfully composed sentence in Greek, but it must be broken into shorter segments for English idiom. It begins with several subordinate phrases (since we have confidence and a great priest), has three parallel exhortations as its main verbs (let us draw near, hold, and take thought), and concludes with several subordinate phrases related to the final exhortation (not abandoning but encouraging).