Matthew 5:47 And if ye salute your brethren only, what do ye more than others? do not even the publicans so? [kjv]
και εαν ασπασησθε τους αδελφους υμων μονον τι περισσον ποιειτε ουχι και οι εθνικοι τοαυτο ποιουσιν [gnt]
There are (at least) two ancient Greek words for what some would call
"cheers" or
"greetings". The ancient Greek word
"ἀσπάζομαι" ≈ "cheers, salute" and is less formal and less serious sense. The word for the general
"ethnic" population at large is in most manuscripts rather than the more specific "
publican" or "
tax collector" (which has a special meaning when used by Jesus).
1 Thessalonians 5:16 Rejoice evermore. [kjv]
παντοτε χαιρετε [gnt]
5:17 Pray without ceasing. [kjv]
αδιαλειπτως προσευχεσθε [gnt]
The ancient Greek word
"χαίρετε" ≈ "greetings, rejoice" and is usually in a more formal, sincere and positive sense. The modern Greek word
"χαίρετε" (HEH-reh-teh) ≈ "greetings" as a more formal greeting.