Complex sentence: He was the first one who pledged of allegiance to first caliph Abu Bakr in Saqifa meeting, he well-handled the situation when there was a huge dispute and division on the matter of succession to Prophet.
Split into simpler sentences: He was the first one who pledged of allegiance to the first caliph, Abu Bakr, in a meeting in Saqifa. He wisely handled the situation when there was a huge dispute and division on the matter of succession to Prophet.