Entering Arabic and Farsi language text into After Effects without assistance fails because Arabic flows right-to-left while English flows left-to-right. Simply reversing the text (for example using the TextReverser script) does not work because the letters don't link properly after they are reversed. This script deals correctly with medial letterforms and flows the text from right to left.
Go to the tools panel and select the Horizontal Type tool. Click your image where you would like to insert text and type a phrase. When you’re done, press Escape to exit the text field. Notice that a new layer with your text has appeared in the Layers panel.