Acts 7:22

at length Moses was instructed in all the sciences of the Egyptians, and had great influence by his counsels and actions.

1 Corinthians 2:1-4

As for me, my brethren, when I appear'd among you, it was not to represent to you the divine mystery in sublime language, and with human literature.

2 Corinthians 10:10

(for 'tis objected that my letters are weighty and powerful, but my bodily presence weak, and my preaching

2 Corinthians 11:6

if my language is inelegant, my knowledge is not contemptible; but has been fully display'd among you on all occasions.

Treasury of Scripture Knowledge

Summary

And Moses said unto the LORD, O my Lord, I am not eloquent, neither heretofore, nor since thou hast spoken unto thy servant: but I am slow of speech, and of a slow tongue.

Bible References

Eloquent

1 Corinthians 2:1
As for me, my brethren, when I appear'd among you, it was not to represent to you the divine mystery in sublime language, and with human literature.
2 Corinthians 10:10
(for 'tis objected that my letters are weighty and powerful, but my bodily presence weak, and my preaching
2 Corinthians 11:6
if my language is inelegant, my knowledge is not contemptible; but has been fully display'd among you on all occasions.