Salaam.
بسم الله الرحمن الرحيم بخط الثلث
The image above contains "BISMILLAH", written in Sulus Script.
There are 3 "Alif" and 2 "Lam" which create a vertical symmetry. The elongated "Seen" in "Bism" compliments the vertical symmetry of "Alif" and "Lam". The "Meem" of "ar-Raheem" gives the composition a balance. The over-all pyramid like shape is achieved by placing "Eraab" above "ar-Raheem".
Salaam.