Answer by taking a quote from the following article:

Wladyslaw Gomulka (Polish: [vwa'diswaf go'muwka]; 6 February 1905 - 1 September 1982) was a Polish communist politician. He was the de facto leader of post-war Poland until 1948. Following the Polish October he became leader again from 1956 to 1970. Gomulka was initially very popular for his reforms; his seeking a "Polish way to socialism"; and giving rise to the period known as "Gomulka's thaw".

In the fall of 1943, the PPR leadership began discussing the creation of a Polish quasi-parliamentary, communist-led body, to be named the State National Council (Krajowa Rada Narodowa, KRN). After the Battle of Kursk the expectation was of a Soviet victory and liberation of Poland and the PPR wanted to be ready to assume power. Gomulka came up with the idea of a national council and imposed his point of view on the rest of the leadership. The PPR intended to obtain consent from the Cominterm leader and their Soviet contact Georgi Dimitrov. However, in November the Gestapo arrested Finder and Malgorzata Fornalska, who possessed the secret codes for communication with Moscow and the Soviet response remained unknown. In the absence of Finder, on 23 November Gomulka was elected general secretary (chief) of the PPR and Bierut joined the three-person inner leadership.  The founding meeting of the State National Council took place in the late evening of 31 December 1943. The new body's chairman Bierut was becoming Gomulka's main rival. In mid-January 1944 Dimitrov was finally informed of the KRN's existence, which surprised both him and the Polish communist leaders in Moscow, increasingly led by Jakub Berman, who had other, competing ideas concerning the establishment of a Polish communist ruling party and government.  Gomulka felt that the Polish communists in occupied Poland had a better understanding of Polish realities than their brethren in Moscow and that the State National Council should determine the shape of the future executive government of Poland. Nevertheless, to gain a Soviet approval and to clear any misunderstandings a KRN delegation left Warsaw in mid-March heading for Moscow, where it arrived two months later. By that time Stalin concluded that the existence of the KRN was a positive development and the Poles arriving from Warsaw were received and greeted by him and other Soviet dignitaries. The Union of Polish Patriots and the Central Bureau of Polish Communists in Moscow were now under pressure to recognize the primacy of the PPR, the KRN and Wladyslaw Gomulka, which they ultimately did only in mid-July.  On 20 July, the Soviet forces under Marshal Konstantin Rokossovsky forced their way across the Bug River and on that same day the combined meeting of Polish communists from the Moscow and Warsaw factions finalized the arrangements regarding the establishment (on 21 July) of the Polish Committee of National Liberation (PKWN), a temporary government headed by Edward Osobka-Morawski, a socialist allied with the communists. Gomulka and other PPR leaders left Warsaw and headed for the Soviet-controlled territory, arriving in Lublin on 1 August, the day the Warsaw Uprising erupted in the Polish capital.

did he oppose gomulka?
Bierut was becoming Gomulka's main rival.