What supports the implied-mushākalah interpretation of ṣibghat Allāh?

Murāʿāt al-Naẓīr, Corresponding Endings, Irṣād and Mushākalah

• Two explicit occurrences of ṣibgh in the same expression
• The association comes merely from rhyme
• Taking faith as entirely unrelated to the preceding setting
• A known ritual dyeing/immersion background is answered by the language of faith